epubs.surrey.ac.ukepubs.surrey.ac.uk/808903/15/EThesis_6154083.doc · Web viewIntegrating such theories into treatment models may help to further understand OCD from both clinician

EFFECT OF ANXIETY & MEMORY STRATEGIES ON MEMORY IN OCD

URN: 6154083

Memory Deficits in OCD:

The Impact of Spontaneous Organisational Memory

Strategy Use and Anxiety on Memory Performance and

Metamemory

Kate BallaSubmitted for the Degree of

Doctor of Psychology

(Clinical Psychology)

School of PsychologyFaculty of Health and Medical Sciences

University of Surrey

Guildford, Surrey

United Kingdom

September 2015

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URN: 6154083

Abstract

Research into memory performance in OCD has produced largely inconsistent findings. One

potential explanation is that impaired memory performance is secondary to executive

dysfunction and metamemory processes, including deficits in using organisational memory

strategies, reduced memory confidence, and familiarity (remember/know) judgments of the to

be remembered items, as well as the emotional state of anxiety. This explanation was

investigated by comparing the performance of an OCD group (n=17) and a nonclinical

control group (n=17) in a combined verbal and nonverbal memory recall/recognition task.

Findings showed that memory recall and recognition accuracy were comparable between

groups. However, the OCD group used less organisational memory strategies for words and

had higher memory decay from immediate to delayed recall compared to nonclinical controls.

There was no difference for pictures. This effect was enhanced after state anxiety was

controlled, indicating that executive system impairments might be more linked to OCD than

state anxiety. Memory confidence was significantly lower in the OCD than control group but

this difference disappeared after state anxiety was controlled. Overall, these findings suggest

that organisational strategy use is deficient and that confidence is reduced in OCD, which

impacts memory performance. State anxiety levels had a differential effect on these deficits.

Clinical applications of the findings are discussed and careful consideration is given to the

limitations.

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Acknowledgements

I would like to thank all of my tutors, supervisors, colleagues, family and friends for their

endless support throughout my clinical training experience. I would also like to thank my

clinical placement supervisors for offering really valuable experiences and challenging me in

order to aid my development and scaffold my learning. Specifically in relation to my

research, I would like to thank my research supervisors Dr Ellen Seiss, Dr Clara Strauss and

Dr Jason Spendelow; I would also like to thank Dr Lynne Drummond and Dr David Veale

and their respective teams for their support in participant recruitment. Finally, I express

endless thanks to my wonderful family and friends, who have provided me with support,

encouragement and motivation.

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Contents

Abstract............................................................................................................................................. 2

Acknowledgements....................................................................................................................... 3

Contents............................................................................................................................................. 4

MRP Empirical Paper.................................................................................................................. 10

Abstract........................................................................................................................................... 11

1. Introduction.............................................................................................................................. 13

1.1 OCD....................................................................................................................................................... 13

1.2 OCD Models........................................................................................................................................ 13

1.2.2 Neuropsychological models...................................................................................................................14

1.3 Metamemory & OCD....................................................................................................................... 20

1.4 State anxiety...................................................................................................................................... 21

1.5 The current study............................................................................................................................ 22

1.6 Hypotheses........................................................................................................................................ 23

1.6.1 Primary hypotheses...................................................................................................................................23

1.6.2 Secondary hypotheses..............................................................................................................................23

2. Methods...................................................................................................................................... 24

2.1 Participants....................................................................................................................................... 24

2.2 Measures............................................................................................................................................ 27

2.3 Materials............................................................................................................................................. 28

2.4 Procedure........................................................................................................................................... 30

2.4.1 Screening procedure (Part 1)................................................................................................................30

2.4.2 Experimental procedure (Part 2)........................................................................................................30

2.5 Design & Data analysis...................................................................................................................34

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3. Results........................................................................................................................................ 34

3.1 Tests of normality........................................................................................................................... 35

3.2 State anxiety..................................................................................................................................................... 35

3.3 Memory recall................................................................................................................................... 36

3.3.1 Recall accuracy............................................................................................................................................ 37

3.3.2 Organisational memory...........................................................................................................................38

3.3.4 Summary of memory recall findings..................................................................................................41

3.3 Memory recognition accuracy (d’ prime)...............................................................................42

3.4 Metamemory..................................................................................................................................... 43

3.4.1 Memory confidence...................................................................................................................................43

3.4.2 Familiarity judgements (Remember Know Guess)......................................................................46

3.4.4 Summary of metamemory results.......................................................................................................47

4. Discussion.................................................................................................................................. 48

4.1 Summary of key findings.............................................................................................................. 48

4.2 Theory and previous literature..................................................................................................49

4.2.1 Previous research.......................................................................................................................................49

4.2.2 Memory & executive functioning models........................................................................................51

4.3 Theoretical clinical models & clinical application...............................................................52

4.4 Further limitations & future research.....................................................................................55

4.5 Conclusions........................................................................................................................................ 57

References...................................................................................................................................... 58

List of Tables................................................................................................................................. 65

Table 1. Inclusion and exclusion criteria for participant groups.......................................65

Table 2. Demographic and clinical characteristics of participant groups......................65

List of Figures................................................................................................................................ 66

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Figure 1. Visual representation of the experimental task....................................................66

Figure 2. Study phase for the verbal memory task.................................................................66

Figure 3. Study phase of the nonverbal memory task...........................................................66

Figure 4. State anxiety scores (categorisation) for words and pictures across

immediate and delayed time intervals...........................................................................................66

Figure 5. Memory recall accuracy scores for pictures and words across immediate

and delayed time intervals.................................................................................................................. 66

Figure 6. Organisational memory score (total) for words and pictures across

immediate and delayed time intervals...........................................................................................66

Figure 7. Organisational memory score (categorisation) for words and pictures

across immediate and delayed time intervals..............................................................................66

Figure 8. d’ prime scores for words and pictures, which indicates recognition

accuracy. 66

Figure 9. Confidence ratings for words and pictures by list type......................................66

Figure 10. Mean confidence ratings for words and pictures, independent of list type

66

Figure 11. Pictures: Proportion of Remember, Know and Guess familiarity

judgements for Hits on the recognition task.................................................................................66

Figure 12. Words: Proportion of Remember, Know and Guess familiarity judgments

for Hits on the recognition task......................................................................................................... 67

List of Appendices........................................................................................................................ 68

Appendix A: Poster advertisements.................................................................................................71

(i) Clinical OCD group.......................................................................................................................................... 71

(ii) Control group...................................................................................................................................................72

Appendix B: Favourable ethical opinion........................................................................................73

(i) University if Surrey ethics committee....................................................................................................73

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(ii) NHS National Health Research Authority – NRES South Coast, Surrey..................................74

Appendix C: Measures (Part 1).......................................................................................................... 75

(i). Demographics..................................................................................................................................................75

(ii) NART....................................................................................................................................................................76

(iii) MINI.................................................................................................................................................................... 77

(iv) MMSE..................................................................................................................................................................79

(vi) PHQ9................................................................................................................................................................... 81

(vii) STAI – Trait anxiety.....................................................................................................................................82

Appendix D: Measures (Part 2)..........................................................................................................83

(i) STAI – State anxiety........................................................................................................................................83

(ii) Visual Analogue scale for memory confidence..................................................................................84

Appendix E: Stimuli................................................................................................................................ 85

(i) Nonverbal stimuli selection including examples...............................................................................85

(ii) Verbal stimuli selection including examples......................................................................................89

(iii) Filler task examples.....................................................................................................................................94

Appendix F: Participant Forms.......................................................................................................... 95

(i) Information sheet (Clinical OCD group)................................................................................................95

(ii) Participant Information Sheet (Control group)................................................................................98

(iii) Consent form................................................................................................................................................101

Appendix G Data................................................................................................................................... 104

(i) ANOVA results................................................................................................................................................104

(ii) ANCOVA results............................................................................................................................................110

(iii) Skewness and Kurtosis............................................................................................................................114

Appendix H: Journal of Anxiety Disorders - Publication guidance for authors..............121

Major Research Proposal........................................................................................................ 133

Introduction................................................................................................................................ 134

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Research Question.................................................................................................................... 136

Method.......................................................................................................................................... 137

Participants............................................................................................................................................ 137

Design...................................................................................................................................................... 139

Measures................................................................................................................................................. 140

Procedure............................................................................................................................................... 141

Ethical considerations............................................................................................................. 144

R&D Considerations................................................................................................................. 146

Proposed Data Analysis.......................................................................................................... 146

Service User and Carer Consultation / Involvement.....................................................146

Feasibility Issues....................................................................................................................... 147

Dissemination strategy........................................................................................................... 148

Study Timeline........................................................................................................................... 148

MRP Systematic Literature Review..................................................................................... 153

Abstract........................................................................................................................................ 154

Introduction................................................................................................................................ 155

Methods........................................................................................................................................ 158

Search Strategy..................................................................................................................................... 158

Inclusion criteria.................................................................................................................................. 159

Results.......................................................................................................................................... 159

Nonverbal memory and organisation tasks................................................................................160

Summary of RCFT findings.............................................................................................................................165

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Summary - nonverbal memory and organisation tasks.....................................................................167

Verbal memory and organisation tasks.......................................................................................168

Summary – verbal memory and organisation tasks............................................................................171

Verbal, nonverbal memory and organisation tasks.................................................................172

Summary – verbal, nonverbal memory and organisation tasks.....................................................176

Discussion.................................................................................................................................... 178

Conclusions................................................................................................................................. 182

References................................................................................................................................... 184

Appendix 1.................................................................................................................................. 188

Table 1..................................................................................................................................................... 188

Table 2..................................................................................................................................................... 191

Clinical Experience................................................................................................................... 193

Assessments................................................................................................................................ 198

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MRP Empirical Paper


The Impact of Spontaneous Organisational Memory Strategy Use and Anxiety on Memory

Performance and Metamemory

By

Kate Balla

Word Count: 9970

Submitted in partial fulfillment of the degree of

Doctor of Psychology (Clinical Psychology)

School of Psychology

Faculty of Health and Medical Sciences

University of Surrey

July 2015

© Kate Balla

This article is intended for submission to the Journal of Anxiety Disorders

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Abstract

Research into memory performance in OCD has produced largely inconsistent findings. One

potential explanation is that impaired memory performance is secondary to executive

dysfunction and metamemory processes, including deficits in using organisational memory

strategies, reduced memory confidence, and familiarity (remember/know) judgments of the to

be remembered items, as well as the emotional state of anxiety. This explanation was

investigated by comparing the performance of an OCD group (n=17) and a nonclinical

control group (n=17) in a combined verbal and nonverbal memory recall/recognition task.

Findings showed that memory recall and recognition accuracy were comparable between

groups. However, the OCD group used less organisational memory strategies for words and

had higher memory decay from immediate to delayed recall compared to nonclinical controls.

There was no difference for pictures. This effect was enhanced after state anxiety was

controlled, indicating that executive system impairments might be more linked to OCD than

state anxiety. Memory confidence was significantly lower in the OCD than control group but

this difference disappeared after state anxiety was controlled. Overall, these findings suggest

that organisational strategy use is deficient and that confidence is reduced in OCD, which

impacts memory performance. State anxiety levels had a differential effect on these deficits.

Clinical applications of the findings are discussed and careful consideration is given to the

limitations.

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URN: 6154083

Keywords: OCD; Memory; Organisational strategy; Metamemory; Confidence; State anxiety

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1. Introduction

1.1 OCD

Obsessive Compulsive Disorder (OCD) is characterised by recurrent and persistent unwanted

obsessions1 and/or repetitive physical or mental compulsions2 that are time consuming, cause

marked distress and interfere significantly with daily functioning (Diagnostic Manual of

Mental Disorders 5th edition, American Psychiatric Association, 2013). Obsessions involve,

but are not limited to the fear of contamination or doubts about past actions, which often

leads to compulsive behaviours such as repetitive washing and checking behaviours.

Prevalence rates of OCD in the UK are estimated to be 1.2%, with a lifetime prevalence of

2.5% (National Institute for Clinical Excellence, NICE, 2005) and it shares high comorbidity

levels with Axis I disorders such as anxiety and depression (Segalas et al., 2008).

1.2 OCD Models

1.2.1 Cognitive and behavioural models.

The development and maintenance of OCD has been heavily researched (de Silva &

Rachman, 1992; Salkovskis, 1985). Behavioural models suggest that obsessions and

compulsions are learned responses to a fear that was developed via association (de Silva &

Rachman, 1992). Compulsive behaviours that aim to reduce distress, negatively reinforces

the fear by providing a temporary reduction in anxiety, and therefore OCD is maintained.

Cognitive theories emphasise the importance of the misinterpretation of intrusive thoughts.

1 Obsessions: intrusive thoughts, impulses or images that cause significant distress to the individual.

2 Compulsions: repetitive behaviours or mental acts aimed at neutralising the obsession with the aim of reducing the level of distress

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Due to the high levels of distress that is triggered, neutralising behaviours, such as avoidance

and compulsions follow (Salkovskis, 1985). In applying these theories to treatment models,

Cognitive Behavioural Therapy (CBT) is effective in treating OCD relative to placebo and

wait-list conditions at post-treatment and follow-up intervals (Olatunji, Davis, Powers &

Smits, 2013), and is the recommended treatment of OCD in the UK (National Institute for

Health and Clinical Excellence, 2005).

1.2.2 Neuropsychological models.

1.2.2.1 Memory.

Neuropsychological theories of OCD and research are based upon clinical

observations and emphasise the importance of attention, executive functioning and memory.

Integrating such theories into treatment models may help to further understand OCD from

both clinician and client perspectives and further improve treatment outcomes.

One important neuropsychological process that has been investigated in OCD is

memory. Early studies proposed a global memory deficit3 in OCD, which is not surprising

given that chronic doubting, is commonly reported (Sher, Frost & Otto, 1983). However, this

hypothesis is now largely dismissed due to high levels of inconsistency in recent OCD

memory literature (Jelinek, 2006), which are likely to be explained by important factors such

as stimulus material, executive function usage and OCD subtype (e.g. checkers). These will

be discussed in more detail in the next sections.

3 Memory deficit exists regardless of modality

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1.2.2.2 Memory and executive functions.

Recent reviews show that memory difficulties are more likely to occur in tasks that

require high levels of binding4 complexity, more executive functioning efficiency5 and high

levels of memory load6, suggesting that these neuropsychological processes play an important

role in memory functioning (Harkin, Rutherford & Kessler, 2011; Kuelz, Hohagen &

Voderholzer, 2004). Harkin and Kessler (2011) proposed that memory impairment may exist

due to deficits in these three systems or due to a modulated interaction between them. For

example, increased memory load cannot be processed when executive efficiency is

compromised, which then makes binding processes less accurate. Thus, memory performance

is compromised when executive systems are inefficient. Consequently the role of executive

dysfunction on memory has been researched as a potential primary deficit in OCD. This is

also in line with neurobiological models of OCD, which suggest a dysfunction of frontal-

striatal loops that are linked to reward-based learning and executive function (Rauch &

Baxter, 1998).

In parallel researchers began to investigate whether people with OCD have difficulty

in the efficient use of memory strategies7, such as memory organisation (an area closely

4 Binding: Memory process that brings together different complex features of a memory experience, such as features of an object, spatial location and the context in which the item is embedded. Binding complexity relates to how difficult it is to bind different features together. Typically visuospatial tasks are high in binding complexity, whereas verbal memory tasks that do not have spatial information are low in binding complexity.

5 Executive function efficiency: The ability to use the executive function system (e.g. attention, working memory, initiation of strategies) to aid memory process, e.g. to be able to selectively attend to important information, suppress attention to irrelevant information, hold information in mind, use strategies, and reduce outside interference.

6 Memory load: As the level of load/demand increases, more executive strategies are required to process information into memory. E.g. number of items to be remembered: as these increase the load increases; however if the items are semantically related then the load is reduced as stress on the correct implementation of executive strategies is reduced.

7 Memory strategies: the ability to identify and use semantic and perceptual features of stimuli to aid memory recall

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related to executive function), which highlights the intertwined relationship between memory

and executive functions. Strategic memory tasks have an embedded structure and coherent

form, meaning that features of the target item can be used to better encode and organise the

information, for example items might be able to be categorised or pictures may have salient

features. This usually leads to better memory retention of the information. Finally, recent

literature suggests that metamemory processes, including memory confidence and familiarity,

are affected in OCD too (Cutler & Graf, 2009).

The current project will investigate organisational memory strategies and

metamemory in a combined recall/recognition memory task with OCD-relevant and neutral

visual and verbal material, while controlling for state anxiety as a covariate. The next sections

of the introduction will discuss and critique relevant research in more detail whilst arguing

for the relevance of a research project that integrates all these aspects of memory research

into one study to be able to better understand memory deficits in OCD.

1.2.2.2.1 Nonverbal organisational memory & OCD.

Organisational memory strategies have been investigated in several nonverbal and

verbal memory tasks, which were conducted either in different studies or within the same

study. Savage et al., (1998) were the first researchers to question whether nonverbal memory

deficits in OCD are mediated by organisational strategy use. They found that although the

OCD group (n= 20) demonstrated good memory retention of nonverbal information over a

delay when using the Rey Osterrieth Complex Figure Test (RCFT; Rey, 1941), they

performed significantly worse than the nonclinical control group (n= 20) on memory

accuracy and organisational scores. This points to a deficit at encoding rather than storage or

retrieval, which might relate to Harkin and Kessler’s (2011) model of an impaired executive

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system which impacts memory performance as a result of poor encoding, i.e. lack of

executive efficiency at initial presentation of target stimuli. Significant correlations between

RCFT copy organisation scores and recall scores were reported, which indicated that

organisational deficits at encoding are related to impaired nonverbal memory recall. Further

studies have reported similar findings (Nedeljkovic et al., 2009; Penades, Catalan, Andres,

Salamero & Gasto, 2005; Shin, Park, Kim & Lee, 2004; Jang et al., 2010). However the latter

two studies did not report a mediating role of organisational memory strategy use on overall

memory recall performance.

Nevertheless, Jang et al., (2010) found that reduced use of organisational strategies

was related to high scores on the checking subscale of the Yale Brown Obsessive Compulsive

Scale (YBOCS, Goodman et al., 1989). The finding of an enhanced deficit in OCD-checkers

provides evidence for the argument that OCD should be viewed as a heterogeneous disorder

(Lochnor & Stein, 2003) and as such OCD patients are often classified according to their

obsessions and compulsions, such as checkers, washers and obsessionals.

1.2.2.2.2 Verbal organisational memory & OCD.

As the majority of research into verbal memory and OCD has reported comparable

memory performance between OCD and nonclinical control samples (Kuelz, 2004), few

studies have solely assessed the use of organisational memory strategies for verbal memory

tasks. However, organisational memory deficits might be more general in OCD; and therefore

independent of material type. Deckersbach et al., (2004) used the Californian Verbal

Learning Test (CVLT; Delis, Kramer, Kaplan, & Ober, 1987) to compare organisational

strategy use in three age, gender and education-matched sample groups: OCD patients (n=

30), bipolar I patients (n= 30), and nonclinical controls (n= 30). Additionally, the clinical

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groups were matched for age of onset and illness duration. The OCD sample were

significantly impaired in delayed memory recall and used significantly fewer organisational

strategies, meaning they were less likely to cluster words by semantic category. Furthermore

delayed recall performance was mediated by the reduced use of organisational strategies

during encoding. In a follow up study Deckersbach et al., (2005) used an auditory verbal

encoding paradigm whereby word lists were presented in 3 conditions: spontaneous –

participants were not informed that the words could be categorised; directed – participants

were informed that the words could be categorised; unrelated – words could not be

categorised and participants were aware of this. The OCD group (n= 20) were less likely than

the nonclinical control group (n= 20) to spontaneously implement organisational strategies.

1.2.2.2.3 Nonverbal & verbal organisational memory in OCD.

Few studies have used within-participant designs to directly compare nonverbal and

verbal organisational memory abilities. For example, Savage et al., (2000) used the RCFT

and the CVLT to compare organisational strategy use in nonverbal and verbal memory. The

OCD group (n= 33) were significantly impaired on free recall of both material types in

comparison to the nonclinical controls (n= 30), and this was mediated by reduced

spontaneous organisational strategy use. As the impairments were only present when the

tasks required organisational memory skills, they concluded strategic processing is a primary

deficit in OCD rather than memory abilities per se. Segalas et al., (2008) reported similar

findings. Note, however, Exner et al., (2009) found that although the OCD group (n= 23)

used less organisational memory strategies than the nonclinical control group (n= 22), their

memory recall performance was not compromised on the CVLT and RCFT.

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1.2.2.2.4 Critique of the research presented.

The research presented illustrates that reduced use of organisational memory

strategies might partly explain both nonverbal and verbal memory deficits in OCD. However,

inconsistencies remain and could be explained by study limitations, which make it difficult to

draw firm conclusions about whether memory and organisational strategy impairments are

OCD-specific or not. Limitations include failing to control for the use of medication

(Simpson, Huppert, Lin, Foa & Liebowitz, 2006), comorbid Axis 1 disorders (Savage et al.,

1998; Jang et al., 2010), small sample sizes (Savage et al., 1998; Shin et al., 2004; Savage et

al., 2000; Exner et al., 2009), clustering of subtypes (Savage et al., 1998) and not using

comparative control groups or at least accounting for state anxiety levels (Penades et al.,

2005; Deckersbach et al., 2004, 2005).

Another important limitation might be that the stimuli may not be sensitive enough to

elicit differences between OCD and nonclinical control samples. A review by Coles and

Heimberg (2002) found that people with OCD have an explicit memory bias for OCD-

relevant material; that is people with OCD appear to find it more difficult to forget OCD-

relevant material than nonclinical controls. The function of a bias in relation to threat and

anxiety-related information can be well explained from an evolutionary perspective, as

people are more likely to be hyper-vigilant and retain the threatening information in order to

survive. Therefore, it is important to use OCD-relevant or subtype-specific stimuli, rather

than standardised measures (e.g. RCFT, CVLT) to make the study more sensitive to OCD-

specific fears. This could provide more realistic clinical implications for the understanding

and treatment of OCD. The current study addressed this issue by developing OCD checking-

relevant and neutral material.

Based on the organisational memory literature and related design issues, it is

important that future research further examines spontaneous organisational memory strategies

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and memory recall in OCD. It is also relevant to look at verbal and nonverbal memory

together in one study as they might require different levels of memory binding, memory load

and executive efficiency, and therefore might present differently in relation to memory

performance. OCD specificity of the material is also relevant as well as controlling for state

anxiety (see Section 1.4).

1.3 Metamemory & OCD

Another area indirectly related to memory deficits in OCD is metamemory processes,

such as memory confidence and familiarity, which are typically assessed in memory

recognition tasks. Despite comparable recognition accuracy performance, memory

confidence appears to be impaired in OCD (Woods, Vevea, Chambless & Ute, 2002; Cutler

and Graf, 2009; Constans, Foa, Franklin & Matthews, 1995), especially for OCD-checkers

who doubt their past actions and therefore engage in repetitive checking compulsions, which

suggests this is an important area to consider in OCD memory research.

In addition, OCD patients judge the familiarity of their memories differently (Van den

Hout & Kindt, 2003) as assessed with the ‘remember’/’know’ procedure originally proposed

by Tulving (1985). More specifically, ‘remember’ responses are clear in contextual detail,

vivid and relate the specific recollection of an event. In contrast, ‘know’ memories are just

familiar; a person perhaps might get a feeling that they have seen/heard the information

before but the memory lacks specific contextual details. Tulving (1985) argued that

‘remember’ memories are from the episodic memory system whereas ‘know’ memories relate

more to semantic memory system. Signal detection theories (Macmillan & Creelman, 2004)

suggest that familiarity judgements are based upon a signal that varies along a dimension of

strength, i.e. a memory with a strong signal would lead to a ‘remember’ response, whereas a

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memory that was lower on the signal dimension would lead to a ‘know’ response. Fama and

McNally (2003) reported that memories for past actions were more ‘knowing’ than

‘remembering’ in people with OCD as memory recall lacked vividness and contextual

information. This seems to be especially the case for checkers - Van den Hout and Kindt

(2003) reported that compulsive checking increased familiarity, which in turn led to less

detailed memories being formed as less attention was paid to contextual features of the

checking compulsion. They also found this pattern in nonclinical controls.

In summary, it has been reported that people with OCD lack confidence in their

memory and are more likely to have ‘knowing’ memories for non-checking related material,

therefore memories in OCD may generally be less vivid for both OCD-related and neutral

material, which in turn might lead them to be less confident in their memory performance;

therefore increasing distrust in their memories. Given these findings, the current study

included memory confidence and familiarity measures. In order to be able to assess these

metamemory and organisational memory measures in the same sample a combined memory

recall/recognition task was used.

1.4 State anxiety

Finally, but importantly, OCD is an anxiety disorder and therefore the findings related

to spontaneous organisational memory use and metamemory might not be OCD-specific but

instead driven by anxiety itself which is higher in OCD (Tolin, Wohunsky & Maltby, 2006).

When investigating anxiety one can differentiate between trait anxiety which is defined as

“…a general disposition to experience transient states of anxiety” (Spielberger, 1999) and

state anxiety which is defined as “…a temporary anxiety due to a particular situation or

condition that a person is currently in” (p. 726; Coleman, 2009). As this factor might

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confound findings it is especially important to control for it in memory research. In a small

sample study, Tolin et al., (2001) investigated the effect of both state and trait anxiety on

memory confidence in OCD (OCD sample: n= 14; Nonclinical controls: n= 14).

Interestingly, they found that anxiety was not associated with memory recall confidence. In

the current study, this research is extended by controlling for the effect of state anxiety on

memory performance, organisational memory, and metamemory in a memory

recall/recognition task.

1.5 The current study

In summary, the current study will use a within-participant design to investigate

nonverbal and verbal memory performance in a combined memory recall/recognition task

which is a new way to study OCD memory deficits, and thereby attempt to overcome some of

the highlighted gaps in the OCD memory literature. Firstly, memory recall will be assessed

and the influence of organisational memory strategy use on recall will be investigated.

Secondly, memory recognition accuracy and metamemory processes including memory

confidence and familiarity judgments will be investigated in the same study. Thirdly, OCD-

relevant and neutral stimuli will be used to investigate whether there is an explicit memory

bias for OCD-related stimuli in the memory tasks. Finally, the impact of state anxiety on

these findings will be assessed in order to answer the important question of whether these

memory deficits are OCD-specific or a function of state anxiety.

The nonverbal and verbal memory tasks involve list learning, as this enables a more

direct comparison of categorisation as an organisational memory strategy across the two

modalities.

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1.6 Hypotheses

1.6.1 Primary hypotheses.

Based on the literature presented, for hypothesis one it is predicted that the clinical

OCD group will perform more poorly for memory recall accuracy and will use less

spontaneous organisational memory strategies (e.g. categorisation and recall of the

presentation order) compared to the nonclinical control group. With hypotheses two and

three, for the recognition task the OCD group will perform comparably with the nonclinical

controls for accuracy, but they will have reduced metamemory (memory confidence, memory

familiarity). For example, the nonclinical control group will give more ‘remember’ judgments

and the clinical OCD group will give more ‘know’ and ‘guess’ judgments and OCD

participants will be less confident. Finally, for hypothesis four it is predicted that state anxiety

will reduce group differences for memory accuracy (recall and recognition), spontaneous

organisational memory use, and memory confidence.

1.6.2 Secondary hypotheses.

Related to hypothesis one, the memory recall accuracy differences between groups are

predicted to be stronger for nonverbal compared to verbal material between the groups

because the literature suggests that visual memory is more affected in OCD, and links to

Harkin and Kessler’s (2011) model. Related to hypothesis two recognition memory will also

be better for pictures than words across the groups, given that pictures are dually encoded,

that is they generate both verbal and nonverbal associations when viewed (picture superiority

effect; Paivio, 1986). Strategic memory and metamemory effects might be material specific

(verbal vs. nonverbal), item-specific (OCD-relevant vs. neutral item) or more general.

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2. Methods

2.1 Participants

A G*Power calculation (Faul, Erdfelder, Buchner and Lang 2009) estimated that two

groups with 32 participants each would be needed to achieve sufficient statistical power. This

was for the main effect of OCD group on organisational strategy use and was based on an

effect size of d=0.73 from Deckersbach et al., (2005). This means that this study is

underpowered. Therefore, findings will be interpreted with caution.

Two groups of participants – a clinical OCD group (n= 18) and a nonclinical control

group (n= 20) – took part in the study. They were matched for gender, and intelligence

quotient estimates. Three participants from the nonclinical control group who completed the

study were excluded due to potential confounding effects of medication. One participant was

excluded from the clinical OCD group as their data revealed that they had not completed the

experimental memory recognition task correctly. This resulted in the final dataset of 17

participants in each participant group. Please refer to Table 1 for inclusion and exclusion

criteria for participant groups. Table 2 displays the descriptive statistics for each group and

statistical group differences.

Participants in the clinical OCD group were recruited from local hospitals. This was

done via poster advertisement (Appendix Ai) and liaison with involved professionals to

discuss suitability. All participants in the OCD group had a clinical diagnosis of OCD, and

received pharmacological treatment, psychological treatment or a combination of the two.

Due to high levels of co-morbidity between OCD and depression four OCD participants were

experiencing depression at the time of data collection. A number of the participants also met

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diagnostic criteria for agoraphobia (n= 6), panic disorder (n=2), generalised anxiety disorder

(n=2) and social anxiety disorder (n= 1).

Participants in the nonclinical control group were recruited via poster advertisements

(Appendix Aii) at a local university and, at public places, such as local libraries. Although

participants in the nonclinical control group were not experiencing clinical depression at the

time of data collection, a large proportion of the group were experiencing symptoms of low

mood (as measured by the PHQ-9). However, they scored lower than the criteria cut-off point

(Section 2.2 for more detail). Assessments using the Mini International Psychiatric Interview

(MINI; Sheehan et al., 1997) found that one nonclinical control participant had a history of

panic disorder and one had a history of limited symptom panic attacks.

Table 1.

Inclusion and exclusion criteria for participant groups

Clinical OCD group Nonclinical Control group

Inclusion criteria

Age 18+ years 18+ years

First language English English

DSM-IV diagnostic OCD None

OCI-R Total >21 <14

PHQ-9 ≤14 ≤14

MMSE ≥27 ≥27

Exclusion

OCI-R <21 >14

PHQ-9 ≥ 15 ≥ 15

Self-reported neurological

condition

Any Any

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Table 2.

Demographic and clinical characteristics of participant groups

Clinical OCD group

(n=17)

Nonclinical Control

group (n=17)

Gender

Female 9 10

Male 8 7

Mean (SD) Mean (SD) Significance

Age 38.64 (11.94) 29.00 (2.92) u = 75.50, p = .017

FSIQ estimate 115.23 (6.78) 114.80 (4.21) t (32) = 2.16, p = .830

MMSE 29.76 (0.44) 29.44 (0.73)

PHQ-9 11.71 (5.11) 4.41 (2.99) t (32) = 5.09, p <.001

STAI (trait) 60.82 (10.90) 40.53 (12.03) t (32) = 5.16, p <.001

STAI (state) 46.71 (11.04) 32.41 (6.38) t (32) = 4.62, p <.001

OCI-R Total 32.94 (9.70) 8.59 (3.94) t (32) = 9.59, p <.001

Checking 5.88 (3.00) 0.65 (0.70) u = 5.50, p = <.001

Hoarding 3.76 (3.03) 2.94 (2.79) u = 118.00, p = .353

Neutralising 5.00 (4.00) 0.59 (0.87) u = 42, p = <.001

Obsessing 9.00 (3.26) 1.41 (1.77) u = 8.00, p = <.001

Ordering 4.35 (3.94) 2.06 (1.60) u = 99.00, p = .113

Washing 5.76 (4.22) 0.94 (1.09) u = 45.50, p = <.001

Onset (age) 20.92 (8.60)

Diagnosis (age) 22.43 (8.11)

Favourable Ethical Opinions (Appendix B) were received for the study from the

University of Surrey’s Ethics Committee and from the National Health Service Health

Research Authority – NRES South East Coast – Surrey.

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2.2 Measures

The following measures were administered for the purposes of participant screening –

prior to the experimental task (See Appendix Ci-vii).

National Adult Reading Test (NART; Nelson, 1982) – a reading task of 50 irregularly

pronounced words and commonly used as a predictor of verbal IQ. The NART has high

levels of inter-rater reliability (Cronbach’s α = 0.96-0.98) and test-retest reliability (α = 0.98)

and correlates highly with other validated IQ measures (α = 0.85) (Crawford, Parker, Stewart

& De Lacey, 1989).

Mini International Psychiatric Interview (MINI; Sheehan et al., 1997) – a widely used

tool to assess diagnostic status and is considered to be a valid alternative to the Structured

Clinical Interview for DSM-IV consisting of 16 modules covering a range of

neuropsychiatric conditions.

Mini Mental State Exam (MMSE; Folstein et al., 1975) - a brief 30-item screening

assessment of cognitive impairment. It assesses cognitive functions such as attention,

memory, orientation and language. Scores of <27 indicate an underlying cognitive

impairment. Reliability and internal consistency estimates are high α = 0.77 (Tombaugh &

McIntye, 1992).

OCI-R (Foa et al., 2002) – an 18-item self-report measure of obsessive compulsive

symptoms that yields an overall score (range 0-72) and has six subscale scores for washing,

checking, ordering, obsessing, hoarding and neutralising. Scores >20 indicate a likely

presence of OCD. It has good internal consistency (α = 0.81) and test-retest reliability

(ranged from α = 0.74-0.91; Foa et al., 2002).

Patient Health Questionnaire 9 (PHQ-9; Kroenke, Spitzer & Williams, 2001) – a 9-

item self-report measure that corresponds with DSM-IV criteria for major depressive

disorder. Each item is rated for severity on a 4-point scale in relation to symptom frequency.

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Total scores range from 0 (no depression) to 27 (severe depression). It has excellent internal

reliability (α = 0.89; Kroenke et al., 2001)

Spielberger State Trait Anxiety Inventory (STAI; Spielberger, Gorsuch, Lushene,

Vagg & Jacobs, 1983) – a 40-item self-report measure of state and trait anxiety. Each

component has 20 items. The STAI has high internal consistency (α = 0.86-0.95) and test-

retest reliability (α = 0.65-0.75; Spielberger et al., 1983). Trait anxiety was recorded during

screening.

The following were used during the experimental task (Appendix D.i-ii):

Spielberger State Trait Anxiety Inventory (Spielberger et al., 1983) – The state anxiety

questionnaire was completed four times during the experimental task. Reliability and validity

coefficients are above.

Visual Analogue Scales: Participants rated their memory confidence for recognition

items on a scale of 1-10 (1 Low confidence to 10 high confidence).

2.3 Materials

Verbal and nonverbal OCD-relevant stimulus validation. Verbal and nonverbal

OCD-relevant stimuli were piloted prior to experimental use and rated by OCD experts for

valence; their relevance to OCD checking and contamination behaviour; concreteness and

imaginability8. See Appendix Ei-ii for ratings, examples and selection criteria.

Neutral stimuli selection. The neutral stimuli used in the study was selected based on

them belonging to clear neutral semantic categories, for example: furniture, animals, musical

8 Definitions taken from Richards et al., (In preparation) with permission: Concreteness - the extent to which participants thought the word/picture represented an item, i.e. items or concepts than can be sensually experienced as compared to items or concepts that were abstract. For example a word like ‘asparagus’ might be a concrete word, whereas a word like ‘bridging’ might be more abstract. Imaginability (for words only) - the extent to which the word could be conjured up as an image in the participants mind. For example, a word like ‘cupboard’ conjures up a more defined image than a word like ‘harm’.

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instruments, vegetables, transport. As similar categories are used in standardised memory list

tasks (e.g. the CVLT) and due to time restrictions, piloting ratings were not developed.

Nonverbal Stimuli. A pool of fifty pictures taken from the IAPS database (Lang,

Bradley & Cuthbert, 2005) or Google search engine - 40 neutral and 10 OCD-relevant.

Ratings are as follows: positive valence (M= 3.60) negative valence M= 5.97; OCD checking

relevance M= 7.45;). In the study phase a pool of 25 pictures were used: twenty neutral

(linked to four neutral categories) and five OCD-relevant words. During the recognition

phase a pool of fifty pictures were used: 40 neutral (linked to four neutral categories) and 10

OCD-relevant words

Verbal Stimuli. Similarly a pool of fifty words were taken from Bradley and Lang

(1999) and Richards et al., (in preparation) – 40 neutral and 10 OCD-relevant Ratings are as

follows: word length (M= 4.8), valence (M= 3.30), frequency (M= 54.80) and OCD checking

relevance (M= 9.06). In the study phase a pool of 25 words were used: twenty neutral (linked

to four neutral categories) and five OCD-relevant words. During the recognition phase a pool

of fifty words were used: 40 neutral (linked to four neutral categories) and 10 OCD-relevant

words.

Filler Tasks. A series of paper based visual aptitude questions which assessed

learning strategies were used to provide a task during the time delay between the two

experimental time points, and also to prevent participants from rehearsing studied materials

which may aid recognition.. The performance in this task was not analysed. See Appendix

Eiii for examples.

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2.4 Procedure

2.4.1 Screening procedure (Part 1).

Potential participants, mainly from the South of England, who expressed an interest in

the study, were sent a detailed information sheet (Appendix Fi-ii). Participants were then

contacted by telephone or email (based on their preference) to discuss the research further

and prior to giving written informed consent (Appendix Fiii). Afterwards, they were sent the

web link to the online screening questionnaire (Part 1), which was used to assess suitability to

continue to Part 2. The online questionnaire included all screening measures in addition to a

brief demographics questionnaire (Appendix Ci). Participants who met the inclusion criteria

were allocated to the appropriate experimental group and invited to participate in Part 2.

Excluded participants were informed of this and were given the opportunity to ask any

questions. OCD participants had the option of the researcher travelling to the inpatient

setting, provided there was an appropriate room available to complete the research, during

which Part 1 and Part 2 were completed together.

2.4.2 Experimental procedure (Part 2).

The MINI was administered at the beginning of Part 2. The order of the verbal and

nonverbal memory tasks was counterbalanced across participants and stimulus items (OCD-

related vs. neutral) were randomly presented within each task. Instructions for the memory

task were presented on a computer screen. The nonclinical control group participants

completed the experimental task in a quiet behavioural laboratory that was minimised for

distractions where possible. The clinical OCD group completed the experimental task in a

quiet clinician’s office, as participants were part of an inpatient treatment programme.

Verbal memory (Figure 2 for representation of study phase)

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Prior to the memory-encoding phase of the verbal memory task, participants completed the

Spielberger State measure. During the encoding phase, participants were presented with 20

neutral and 5 OCD-related words via speakers. Words were pseudo-randomly presented at

the rate of one per every two seconds in such a way that no two words from the same

category were presented consecutively. Immediately following presentation, participants

were asked to recall as many of the words as possible (immediate recall). Responses were

recorded on a digital recorder and scored by the researcher to ensure accuracy. Afterwards,

participants completed non-memory related filler tasks for 20 minutes. Then, they completed

a second Spielberger state anxiety measure and the delayed recall task. A verbal memory

recognition task followed. Here, participants heard 50 words (25 old, 25 new) and were

instructed to press O for ‘old’ or N for ‘new’ for each word to indicate whether they heard it

before. In all trials, participants were asked to rate their memory confidence on a visual

analogue scale, ranging from 1 (not confident at all) to 10 (very confident), by pressing the

appropriate number. In trials where participants gave an ‘old’ response, they were also asked

to rate their familiarity with the word (remembers, know (familiar), guess).

Nonverbal memory (Figure 3 for representation of study phase)

The visual memory task procedure was very similar to the verbal memory procedure with two

minor differences. Firstly, pictures were presented on a computer screen; pictures were

shown during the encoding phase and 50 pictures during the recognition phase (25 old and 25

new). Secondly, pictures (size 5x5cm) were displayed for 2s with 1s between pictures.

Following the experimental phase of the study, participants were fully debriefed

(Appendix Fiv).

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Figure 1: Visual representation of the experimental task. This is repeated for the verbal and

nonverbal task.

Figure 2: Study phase for the verbal memory task. Note the experimental task included 25

sound clips prior to the recall instructions and this Figure is provided to give a visual

representation of the task.

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Figure 3: Study phase of the nonverbal memory task. Note the experimental task included 25

pictures prior to the recall instructions and this Figure is provided to give a visual

representation of the task.

2.5 Design & Data analysis

The study used a 3x3 mixed factorial design with the within-participant factors of

MATERIAL (pictures vs. words) and CATEGORY (OCD-relevant vs. neutral); and the

between-participant factor of GROUP (clinical OCD vs. nonclinical controls). Separate

mixed ANOVAS were conducted using the following dependent variables: 1) spontaneous

organisational memory use (items correctly categorised; items recalled in the same order as

they were presented), 2) memory accuracy for immediate recall, delayed recall and

recognition (d’ prime), 3) familiarity judgements (remember, know, guess judgements for the

recognition task), 4) memory confidence (confidence in their ability to correctly identify

recognition items as ‘old’ or ‘new’). Significant interactions were further analysed using two-

way ANOVAs or post-hoc t-tests, with Bonferroni corrections applied where necessary

(pcritical = .05/number of tests). Where analysis revealed significant (p <.05) or marginally

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significant (p <.10) main effects or interactions of GROUP, ANCOVAs were used with

STATE ANXIETY as the covariate (mean value across all 4 state anxiety recordings). Only

results with statistical significance (or marginal) are reported (see Appendix Gi for full

results).

3. Results

All responses were recorded and scored by the researcher. For memory accuracy, one

point was scored for each correctly recalled item. For organisational strategy, one point was

scored for each item that was recalled consecutively from the same semantic category, or if

the items were recalled in the same order as presented. Recognition accuracy, measured by d-

prime (d’)9 was calculated from the Hit and False Alarm rates on the recognition task.

Memory confidence was scored on a 1-10 VAS. The number of Remember Know Guess

responses for Hits were also recorded.

3.1 Tests of normality

All dependent variables were checked for their distribution. Inspection of boxplots

revealed a number of variables with outliers (> 2 SD above/below the mean; Field, 2009).

However, this was on less than 20% of the variables and participants were not consistently

9 Macmillan & Creelman’s (2004) signal detection theory states that an individual’s ability to identify an item as

‘old’ or ‘new’ depends on the familiarity (or strength of signal) of the item. A correct identification of an ‘old’

item is a ‘hit’ (H), and incorrect identification of a ‘new’ item as ‘old’ is a ‘false alarm’ (F). d’ calculates the

strength of familiarity (signal), which gives a better indication of actual memory accuracy, calculated by

d'=z(H)-z(F). A higher d’ score indicates greater recognition accuracy.

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scoring >2 standard deviations for many variables. Given the low sample size and low trial

numbers within the experimental task this pattern was very difficult to avoid. Following

advice from a university statistician, parametric tests were used to analyse the dataset because

of a lack of good alternatives to mixed ANOVAs. However, the findings should be

interpreted with utmost caution (See Appendix Gii for skewness and kurtosis z-scores).

3.2 State anxiety

The analysis revealed a main effect of TIME (F(1, 32) = 14.96, p= .001), indicating

that state anxiety was higher at delayed (M = 41.28, SD = 12.76) than immediate recall (M =

37.78, SD = 11.65) and a significant main effect of GROUP (F(1, 32) = 20.21, p < .001),

showing that the OCD group (M = 46.55, SD = 12.07) had higher state anxiety scores than

the nonclinical controls (M = 32.50, SD = 7.38) (Figure 4). As there was no significant

interaction between TIME and GROUP, the state anxiety scores were averaged score and

used for the ANCOVA analyses.

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Figure 4. State anxiety scores (categorisation) for words and pictures across immediate and

delayed time intervals.

3.3 Memory recall

Memory recall dependent variables (recall accuracy, organisation total, categorisation

and presentation order) were analysed using mixed ANOVAs with two within-participant

factors of MATERIAL and TIME and one between-participant factor of GROUP.

3.3.1 Recall accuracy.

The ANOVA revealed main effects of MATERIAL (F(1, 32) = 43.08, p <.001) and

TIME (F(1, 32) = 37.99, p <.001). Participants accurately recalled more pictures (M = 13.19,

SD = 4.32) than words (M = 8.88, SD = 4.33) and accurate recall was higher at the immediate

(M = 11.76, SD = 4.11) than delayed (M = 10.31, SD = 4.54) interval. The clinical OCD and

nonclinical control groups did not significantly differ for memory recall accuracy (GROUP:

F(1, 32) = 1.84, p= .185; Figure 5).

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There was a marginally significant three-way interaction between MATERIAL, TIME

and GROUP (F(1, 32) = 2.94, p= .096). Post-hoc two-way ANOVAs for independent groups

revealed a main effect of TIME for the nonclinical controls (F(1, 16)= 13.59, p= .002)

meaning that they recalled fewer items after a delay compared to the immediate recall

condition. This pattern was replicated in the clinical OCD group (F(1, 16)= 26.11, p <.001)

but the OCD group also had an interaction between TIME and MATERIAL (F(1, 16)= 6.12,

p= .025), caused by a significant recall decay over time for words (t(16) = 5.05, p <.001) but

not for pictures (t(16) = 1.95, p= .069; pcritical = .0125).

The ANCOVA revealed a non-significant effect of the covariate STATE ANXIETY

(F(1, 31) = 1.11, p= .300) meaning that state anxiety does not sufficiently explain the

variance in the data to have grossly influenced the findings.

Figure 5: Memory recall accuracy scores for pictures and words across immediate and


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3.3.2 Organisational memory.

3.3.2.1 Organisational memory strategies (total).

The total organisational memory score was calculated by combining the

categorisation and order of presentation scores. There was a significant main effect of

MATERIAL (F(1, 32) = 29.03, p <.001), as participants organised their memory more for

pictures (M = 9.9, SD = 5.14) than words (M = 5.1, SD = 4.27). There was no significant

difference between the clinical OCD and nonclinical control group for overall organisational

memory strategy use (GROUP: F(1, 32) = .46, p= .504; Figure 6). There was a marginally

significant interaction between MATERIAL and GROUP (F(1, 32) = 2.85, p= .101). Post-

hoc paired sample t-tests revealed a significant difference in organisational strategy use

between words (M = 3.82, SD = 2.77) and pictures (M = 10.24, SD = 5.41) for the OCD

group (t(16) = 5.04, p <.001), but not for the non-clinical controls (t(16) = 2.59, p= .019). For

completeness, independent samples t-tests showed no significant difference between groups

for either words (t(25) = 1.61, p= .119) or pictures (t(32) = .41, p= .685).

The ANCOVA revealed a non-significant effect of the covariate STATE ANXIETY

(F(1, 31) = 2.28, p= .142) meaning that state anxiety does not sufficiently explain the

variance in the data to have influenced the findings. Note that the interaction between

MATERIAL and GROUP became significant (previously marginally significant) after

controlling for STATE ANXIETY (F(1, 31) = 4.39, p= .044), which might be because the

covariate explains a small proportion of the variance in this interaction but not sufficient

amounts to become a significant factor itself.

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Figure 6. Organisational memory score (total) for words and pictures across immediate and


3.3.2.2 Organisational memory strategies (categorisation).

The analysis revealed a main effect of MATERIAL (F(1, 32) = 34.86, p <.001);

specifically participants categorised pictures (M = 9.35, SD = 8.07) more than words (M =

4.28, SD = 4.14). There was no significant difference between the clinical OCD and

nonclinical control group for using categorisation as a memory strategy (GROUP: F(1, 32)

= .38, p= .541; Figure 7).

There was a marginally significant interaction between MATERIAL and GROUP

(F(1, 32) = 3.23, p= .082). However, post-hoc t-tests showed no specific group differences for

words (t(25) = 1.61, p = .119) or pictures (t(32) = -.41, p= .685) but both groups showed a

significant MATERIAL effect (clinical OCD group: t(16) = -5.321, p <.001; nonclinical

control group t(16) = -2.975, p= .009).

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The ANCOVA revealed a non-significant effect of STATE ANXIETY (F(1,31) =

2.23, p=.145) meaning that state anxiety does not sufficiently explain the variance in the data

to have influenced the findings. Importantly the ANOVA interaction between MATERIAL

and GROUP became more significant (F(1, 31) = 4.71, p=.038). Therefore, STATE

ANXIETY might explain a small proportion of the variance in this interaction but not a

sufficient amount to become a significant factor itself.

Figure 7. Organisational memory score (categorisation) for words and pictures across

immediate and delayed time intervals.

3.3.2.3 Organisational memory strategies (presentation order).

The ANOVA revealed no main effects of MATERIAL (F(1, 32) = 1.76, p= .194),

TIME (F(1, 32) = .60, p= .253) or GROUP (F(1, 32) = .41, p= .526) on the use of

presentation order as a memory recall strategy, i.e. recalling information in the order it was

presented during the study phase.

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3.3.4 Summary of memory recall findings.

In both groups’ memory recall was highly influenced by material, i.e. pictures were

better recalled than words, and organisational memory strategies were used more for pictures

than words. Interestingly, the rate of decay between immediate and delayed recall was

reduced for pictures in the clinical OCD group compared to the nonclinical control group.

The clinical OCD group used less organisational strategies for words than pictures; an effect

that was not present for the nonclinical controls. This marginally significant interaction

became more significant after controlling for state anxiety, and therefore other factors are

likely to explain the findings better than state anxiety levels, e.g. OCD-specific symptoms.

3.3 Memory recognition accuracy (d’ prime)

Recognition accuracy was analysed using an ANOVA with two within-participant

factors of MATERIAL and CATEGORY (OCD-related vs. neutral), and one between-

participant factor of GROUP.

The analysis revealed main effects of MATERIAL (F(1, 32) = 72.43, p < .001) and

CATEGORY (F (1, 32) = 14.09, p= .001), indicating that recognition memory was more

accurate for pictures (M = 2.97, SD = .86) than words (M = 1.59, SD = .87), and for OCD-

relevant stimuli (M = 2.51, SD = .99) than for neutral stimuli (M = 2.05, SD = .77). There was

no significant difference between the clinical OCD and nonclinical control group for memory

recognition accuracy (GROUP: F(1, 32) = 1.66, p= .207; Figure 8).

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Figure 8. d’ prime scores for words and pictures, which indicates recognition accuracy .

3.4 Metamemory

Memory confidence was analysed using a mixed ANOVA, with three within-participant

factors MATERIAL, CATEGORY and LIST TYPE (old vs. new items), and the between-

participant factor of GROUP. Additionally, the dependent variable familiarity (on correctly

identified old items from the study phase – Hits) had three levels (FAMILIARITY

JUDGEMENTS: remember, know and guess) to investigate memory familiarity effects.

3.4.1 Memory confidence.

The ANOVA revealed main effects of MATERIAL (F(1, 32) = 42.11, p <.001) and

LIST TYPE (F(1, 32) = 71.41, p <.001), indicating that participants were more confident in

their memory for pictures (M = 8.54, SD = 1.38) than words (M = 6.94, SD = 1.67) and for

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‘old’ (M = 8.49, SD = 1.27) than ‘new’ items (M = 6.99, SD = 1.79). There was a significant

main effect of GROUP (F(1, 32) = 4.37, p= .045), specifically that the clinical OCD group (M

= 7.36, SD = 1.66) were less confident than the nonclinical control group (M = 8.13, SD =

1.27); See Figure 9. The significant two-way interaction between MATERIAL and

CATEGORY (F(1, 33) = 9.16, p= .005) was explained by a larger confidence rating

difference between pictures and words for OCD-relevant compared to neutral items (t(33) =

2.97, p= .006)

The ANCOVA revealed a non significant effect of STATE ANXIETY (F(1, 31) =

1.92, p= .176) meaning that state anxiety did not sufficiently explain the variance in the data

to have influenced the findings. Importantly the main effect of GROUP was no longer

significant (F(1, 31) = .59, p= .450), indicating that the two groups did not differ in memory

confidence when STATE ANXIETY was controlled. An alternative explanation is that the

ANCOVA increased the degrees of freedom, which reduced the likelihood of the GROUP

effect becoming significant. Additionally the interaction between MATERIAL, CATEGORY

and GROUP became significant (F(1, 31) = 4.72, p= .038; see Figure 10). It was non-

significant in the ANOVA (F(1, 31) = 2.33, p= .137). This might be because STATE

ANXIETY explains some of the variance of the interaction but not a sufficient amount to

become significant as a factor itself. However, given the complexity of this interaction it

should be interpreted with caution.

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Figure 9. Confidence ratings for words and pictures by list type (‘old’ or ‘new’).

Figure 10: Mean confidence ratings for words and pictures, independent of list type (old vs.

new).

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3.4.2 Familiarity judgements (Remember Know Guess).

The analysis revealed main effects of FAMILIARITY JUDGEMENTS (F(2, 46) =

123.03, p <.001), specifically after correctly recognising an item participants indicated more

Remember (M = 70.81, SD = 24.47) than Know (M = 22.34, SD = 22.59) than Guess

judgments (M = 6.85, SD = 11.91). There was a significant interaction between MATERIAL

and FAMILIARITY JUDGEMENTS (F(2, 54) = 13.16, p <.001); See Figure 11 for pictures;

Figure 12 for words. Post-hoc t-tests revealed more Remember responses for pictures (M =

80.97, SD = 21.73) than words (M = 60.65, SD = 22.44; t(33)= 4.63, p <.001) and more

Guess responses for words (M = 12.03, SD = 17.49) than pictures (M = 1.67, SD = 4.25; t(33)

= -3.55, p= .001). There was no significant main effect of GROUP (F(1, 32) = .22, p= .641).

Figure 11. Pictures: Proportion of Remember, Know and Guess familiarity judgments for

Hits on the recognition task.

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Figure 12. Words: Proportion of Remember, Know and Guess familiarity judgments for Hits

on the recognition task.

3.4.4 Summary of metamemory results.

The OCD group was less confident in their memory recognition performance than the

nonclinical control group. However, this difference was no longer statistically significant

when state anxiety was controlled for indicating that state anxiety might account for this

group difference in memory confidence. This highlights the importance of recording and

controlling for state anxiety in OCD memory research. However, this interpretation should be

taken with caution, as it could be that the increased degrees of freedom in the ANCOVA

reduced the likelihood of the group effect to maintain significance. For completeness,

familiarity judgments did not differ between groups.

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4. Discussion

4.1 Summary of key findings

The primary hypothesis of this study had several subsections. Firstly, it was predicted that

memory recall and organisational memory would be reduced in OCD. This was partially

supported by the data. Memory recall was similar for both groups but the OCD group showed

more memory decay between immediate and delayed recall for words compared to pictures,

and recall accuracy was numerically lowest in the word condition for OCD participants. The

OCD group also used less organisational strategies in the word compared to the pictures task.

No difference was found for the control groups. Furthermore, this material related group

difference was enhanced after state anxiety was controlled. This is in contrast to the state

anxiety hypothesis, which proposed that OCD group differences can be solely explained by

state anxiety. These findings relate to the power of images and the potential role they play in

the development and maintenance of OCD (see Section 4.3 for further discussion). Both

participant groups reported that the filler tasks were challenging and that they were fully

engaged with the filler task, i.e. they did not rehearse the information presented at encoding

during the delay interval.

Secondly, we predicted that OCD and control groups will not differ in their memory

recognition performance but that the OCD group would be less confident in their memory

recognition and that they will have more ‘know’ than ‘remember’ familiarity judgments

compared to nonclinical controls. The findings were in accordance with the hypothesis. This

memory confidence effect disappeared when state anxiety was controlled, therefore

supporting the state anxiety hypothesis, and suggesting that state anxiety should be more

carefully considered in OCD treatment models as this might have a positive impact of

psychological therapy outcomes (see Section 4.3). There were no group differences for

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familiarity judgments. Both participant groups gave more ‘remember’ judgments for pictures

and more ‘guess’ judgments for words, which may give an indication of the degree of

difficulty for each memory tasks.

When looking at the findings above, the influence of state anxiety was mixed and

therefore partially supported the primary hypotheses – it reduced effects for memory

confidence but, interestingly, enhanced group effect differences in organisational memory

strategy use depending on memory task.

In accordance with the secondary hypothesis, there was a strong effect of material

across participant groups, in that pictures were more accurately recalled and recognised, more

organised (mainly by categories), more accurately recognised, responded to with higher

memory confidence, and created more vivid recollection memories (‘remember’ response).

When looking at OCD-relevant vs. neutral items, memory recall was not affected but

recognition accuracy was higher for OCD-relevant items.

Given that some findings were marginally significant, all results and interpretations

should be taken with caution. This might be due to the current study being underpowered - it

could be hypothesised that with enough participants to achieve sufficient statistical power (n=

32 participants per group) that group differences would become significant. Additionally,

given the number of confounding variables and the difficulty in controlling for them all, it is

possible that other variables share proportions of the variance in the findings.

4.2 Theory and previous literature

4.2.1 Previous research.

The nonverbal organisational memory findings are consistent with Savage et al.,

(1998), who also found that OCD participants had better retention of visual information

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across a delay. However, they also found that the OCD group performed worse than the

control group for both memory recall accuracy and organisational strategy use, whereas the

current study only found reduced organisational strategy usage for words compared to

pictures for the OCD group but not for the controls, which perhaps relates to the ‘picture

superiority effect’ (Paivio, 1986) and that pictures are more easily organised in our minds due

to being dually encoded. Qualitative information gained at the end of the experimental

procedure of the current study confirmed that both participant groups found it easier to

spontaneously implement memory strategies for pictures. Both groups reported using

categorisation, repetition and associations to knowledge from their long-term memory. In

contrast auditory words are more difficult to organise, as there are less external/visual cues

available to aid spontaneous organisation of material. Deckersbach et al., (2004) also reported

reduced strategy use for auditory words, namely semantic clustering in OCD. Interestingly, in

the current study the nonclinical control group reported using other memory strategies during

the word task, such as creating a story, whereas the clinical OCD reported finding it more

difficult to use memory strategies for the word task. It is possible that the current study did

not find group differences for organisational strategy use for pictures and words because the

picture task was too low in memory binding complexity in comparison to previous research

that used the RCFT. The RCFT has a visuospatial load, therefore increased binding

complexity and group differences are frequently reported (Savage et al., 2000). Additionally,

the memory load for the word task in the current study might have been rather high for both

participant groups and therefore the inefficient executive system struggled to manage the

demands. This is an area of limited research, and thus further research with larger sample

sizes and matched difficulty levels between the verbal and nonverbal task is warranted in

order to draw firm conclusions.

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In relation to memory recognition and metamemory, the current study corroborates

previous research that indicated impaired memory confidence in OCD rather than memory

per se (Woods et al. 2002, Constans et al., 1995; Van den Hout & Kindt, 2003). It also links

to the Tolin et al. (2006) study that reported memory confidence differences driven by state

anxiety. For memory familiarity, the current study did not find statistically increased ‘know’

judgments for the OCD group compared to nonclinical controls, which is contrary to the

literature (Fama & McNally, 2003; Van den Hout & Kindt, 2003). Note, however, the

numerical difference between the groups was in the correct direction and might not have

reached statistical significance because the study was underpowered. The finding of more

‘remember’ judgments for pictures and more ‘guess’ judgments for words might relate to

pictures being easier to recall than words, especially as pictures are embedded in contextual

information with distinct features, whereas the auditory word task lacked external

associations as no information was presented on the computer screen.

4.2.2 Memory & executive functioning models.

The current study provides empirical support for Harkin and Kessler’s (2011)

executive functioning model that suggests OCD deficits are especially pronounced in

memory tasks with high levels of binding, memory load, and executive functioning are

required. More specifically, performance for both memory recall and recognition was

reduced for words compared to pictures because (1) the visual picture information was too

low in binding complexity; (2) the memory load was enhanced in the more difficult acoustic

word task because pictures are more distinctive and dually encoded. Furthermore, the results

found that the OCD group was less able to use organisational strategies for words compared

to pictures; a difference that was not present for the nonclinical control group. Therefore, for

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the OCD group, memory load was not sufficiently reduced in the word task due to poor

executive efficiency in the use of organisational strategies, which led to a reduced level of

information processing. This material related group effect was enhanced when state anxiety

was controlled, therefore supporting the hypothesis that memory deficits in OCD can be

explained by impairment in the executive system. The difficulty in matching the two memory

tasks on the three components of the model might explain the lack of group differences found

in this study and indeed other studies. Addressing this design issue in future research is

important for the comparison of verbal and nonverbal memory function in OCD. It is possible

that with a re-evaluated design, the data could meet assumptions of parametric tests and

therefore be more reliably interpreted.

Furthermore, according to Harkin and Kessler’s model attending to threat-relevant

information enhances the memory for this specific information but also compromises

executive efficiency in a memory task. Harkin and Kessler reported that OCD participants in

particular were more prone to this deficit, which would in turn impede memory performance.

However, both groups were more accurate for their recognition of threat-relevant

information. This inconsistency will be discussed in the limitation section (Section 4.4). Of

note was the qualitative information gained at the end of the experimental procedure. The

majority of the clinical OCD group noticed the OCD-relevant category in comparison to a

minority of the nonclinical control group. This suggests that the OCD group were more

hypervigilant to these stimuli, and therefore supports Harkin & Kessler’s model.

4.3 Theoretical clinical models & clinical application

The key findings from the study link to cognitive behavioural models of OCD, which

emphasise the importance of negative appraisals in the experience of distress. Images or

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thoughts appraised as harmful leads to heightened anxiety and the urge to engage in a

compulsive behaviour, which acts as a negative reinforcer and temporarily reduces anxiety

(Rachman, 2002; Salkovskis, 1985). The finding of slower decay of visual information in

OCD might explain the power of intrusive images in OCD maintenance cycles. If a

distressing image is held in the mind for longer a person may be more likely to engage in a

compulsion to provide temporary relief from the anxiety, leading to a cycle that is

increasingly difficult to break. This highlights the need for thorough assessment and

formulation of intrusive images; especially given prevalence is an high as 81% (Speckens,

Hackman, Ehlers & Cuthbert, 2007). Working more with images in therapy is recommended

as both internally driven, i.e. memories of past actions, and externally driven images, i.e. cues

in the environment, are likely to have a powerful effect in triggering anxiety and therefore in

the maintenance of OCD. Further, there could be a role for the inclusion of positive imagery

in OCD treatment models. For example, imagining oneself coping effectively with intrusive

thoughts and/or competently preventing oneself from engaging in compulsive behaviours.

This could lead to positive outcomes, given the finding related to the power of images over

time in OCD.

The metamemory findings of reduced memory confidence (but not recognition

accuracy) and numerically less ‘remember’ responses than the control group further

complement Rachman’s (2002) cognitive model of OCD. They suggest compulsive checkers

have reduced memory confidence due to negative harm and responsibility appraisals and in

an attempt to achieve certainty they engage in repetitive compulsions. Conversely this results

in decreased memory confidence, and has the opposite effect on memory familiarity -

memories become less vivid as compulsions increase. This further perpetuates the problem of

reduced memory confidence and increases uncertainty; increasing the likelihood of engaging

in compulsive behaviours.

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In addition to the aforementioned theoretical links and implications, the finding of

reduced group differences for memory confidence once state anxiety was controlled,

highlights the need to monitor state anxiety levels in therapy. This is especially important

given that memory confidence could play a key role in OCD maintenance cycles. For

example, when in Exposure Response Prevention (ERP10) situations high anxiety levels are

likely to account for reduced memory confidence and, therefore, it is likely to perpetuate the

maintenance cycle. Furthermore, as negative metamemory beliefs exist (i.e. memory distrust

is high), the inclusion of information about metamemory processes and OCD-maintenance to

the psychoeducation component of CBT might be helpful. Linking to Rachman’s (2002)

model, increasing awareness and knowledge of the relationship between the two key

processes of metamemory and compulsive behaviours, as well as highlighting the

inconsistency between memory accuracy and metamemory, might help OCD clients to resist

engaging in compulsions. This could be explored using behavioural experiments, which

might generate evidence against their metamemory beliefs and interrupt the OCD

maintenance cycle. Helping a person to gain insight might increase their understanding of

their difficulties and lead to better therapeutic engagement. The value of adding general

anxiety management in OCD therapy protocols is indicated here, especially given the link

between metamemory processes and the negative impact general anxiety can have on these.

Additionally, helping clients to manage general anxiety levels better might provide a positive

impact on psychological therapy outcomes in OCD.

The OCD group was better able to retain visual information over time, which provides

empirical support for the benefits of the visual representation of therapy material. This is

consistent with good practice in CBT and behavioural models. During therapy sessions

10 ERP: A person is exposed to an anxiety-provoking situation and prevented from engaging in a compulsive behaviour that would ordinarily provide temporary relief from the anxiety

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anxiety levels might be too high for clients to encode, store and therefore later retrieve the

information from memory. Thus, visual representation of information, e.g. plotting graphs of

anxiety levels during ERP sessions or visually recording outcomes from a behavioural

experiment, can be referred to outside of therapy sessions, perhaps at times when anxiety

levels are within the therapeutic window (i.e. the optimal level for engaging in therapeutic

process and also the engagement of the frontal lobes to integrate learning into active testing;

Zull, 2011), which might lead to better retention and reinforce therapy learning points.

The finding of enhanced organisational strategy use after controlling for state anxiety

might point to the inclusion of additional cognitive retraining methods in therapy. Buhlman et

al., (2006) suggested doing this could increase a person’s ability to encode information and

therefore learn in therapy, which might increase the likelihood that memories will be

retrieved during daily activities. A suggestion for usefulness of such a cognitive training

programme comes from Park et al., (2006), who found that OCD symptoms and memory

performance improved after organisational memory training. Further research into the benefit

of cognitive retraining programmes targeting organisational memory strategies is needed.

4.4 Further limitations & future research

Although this study was comprehensive in assessing memory recall, recognition and

metamemory, there are a number of limitations. Low participant numbers (n=17 per group)

meant the study was underpowered, and low trial numbers (n=5 per category) due to the time

restrictions in the experiment design means that all findings and interpretation should be

taken with an element of caution. Given these limitations, the possibility of violating data

normality was high and therefore future studies perhaps could re-evaluate the design, e.g. the

number of categories could be reduced but with more items in each, or the OCD-relevant

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category could have more items. Further design issues (see section 4.2.2) could be addressed

by including a spatial element to the picture task in order to increase the binding complexity,

an item number reduction in the word task to reduce the memory load and a corresponding

item number increase in the picture task.

The study initially wanted to investigate memory performance in OCD-checkers as

research indicated that this subtype might be more prone to memory deficits (Jang et al.,

2010; Nedeljkovic et al., 2009); however due to recruitment constraints the OCD sample was

mainly recruited from inpatient services, where symptom profiles varied. Indeed many

participants reported OCD starting with compulsive checking, but had further developed into

mixed symptomology with increasing OCD duration. This means that even though mixed

symptom profiles are very common in OCD (Segalas et al., 2008), the stimuli used in the

study might not have been sensitive enough to elicit emotional reactions in all OCD

participants. Future studies should aim to use OCD-relevant stimuli and where possible to

develop stimulus sets that can be used with a range of people who experience OCD,

especially given the arguments that OCD should be viewed as a heterogeneous disorder

(Lochnor & Stein, 2003). Although the current study recorded other co-morbidities including

depression, it was impossible to exclude on this basis as depression rates are especially high

in inpatient settings. Therefore, the interpretation of the results should bear in mind that

depression might share some of the variance in accounting for any group differences.

However, some authors argue that doing this is a misrepresentation of the OCD population as

comorbidity with depression could be a part of the OCD symptomology (Segalas et al.,

2008). It is also possible that differences between the participant groups could have been

related to the differences in experimental setting, age or trait anxiety levels. Although one

study that controlled for a wide range of possible confounds including depression, medication

and other diagnoses found that these factors did not influence the findings (Deckersbach et

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al., 2004), future studies with larger participant numbers should aim to conduct the

experiments in the same setting for both participant groups, and better control for such

factors.

4.5 Conclusions

The current study investigated aspects of memory recall, recognition and

metamemory processes (confidence and familiarity) in OCD. Although memory recall and

recognition accuracy was comparable across groups, there were group differences for

organisational memory strategy use, which was enhanced when state anxiety was controlled,

and memory confidence, which disappeared when state anxiety was controlled. The findings

support Harkin and Kessler’s (2011) executive memory model, and complement Rachman’s

(2002) cognitive model of OCD. The importance of the clinical application of these findings

is discussed at length, including the possibility of including cognitive retraining methods

using organisational strategies into existing therapy models, the use of visual materials in

therapy, and the importance of monitoring state anxiety in therapy. Given organisational

memory research in OCD for both picture and word tasks are limited, further research with

larger sample sizes is warranted in order to draw firm conclusions.

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List of Tables

Table 1. Inclusion and exclusion criteria for participant groups

Table 2. Demographic and clinical characteristics of participant groups

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List of Figures

Figure 1. Visual representation of the experimental task.

Figure 2. Study phase for the verbal memory task.

Figure 3. Study phase of the nonverbal memory task.

Figure 4. State anxiety scores (categorisation) for words and pictures across


Figure 5. Memory recall accuracy scores for pictures and words across immediate

and delayed time intervals.

Figure 6. Organisational memory score (total) for words and pictures across


Figure 7. Organisational memory score (categorisation) for words and pictures

across immediate and delayed time intervals.

Figure 8. d’ prime scores for words and pictures, which indicates recognition

accuracy.

Figure 9. Confidence ratings for words and pictures by list type.

Figure 10. Mean confidence ratings for words and pictures, independent of list type

Figure 11. Pictures: Proportion of Remember, Know and Guess familiarity

judgements for Hits on the recognition task.

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Figure 12. Words: Proportion of Remember, Know and Guess familiarity judgments

for Hits on the recognition task.

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List of Appendices

A Poster advertisements

(i) Clinical OCD group

(ii) Control group

B Favourable Ethical Opinion

(i) University of Surrey

(ii) NHS National Health research Authority – NRES South East Coast

C Measures (Part 1 of study)

(i) Demographics

(ii) National Adult Reading Test

(iii) Mini International Neuropsychiatric Interview

(iv) Mini Mental State Examination

(v) Obsessive Compulsive Inventory – Revised

(vi) Patient Health Questionnaire 9

(vii) Spielberger State Trait Anxiety Inventory – Trait version

D Measures (Part 2 of study)

(i) Spielberger State Trait Anxiety Inventory – State version

(ii) Visual analogue scale for confidence ratings

E Stimuli

(i) Nonverbal stimuli selection including examples

(ii) Verbal stimuli including examples

(iii) Filler task examples

F Participant forms

(i) Information sheet (Clinical OCD group)

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(ii) Information sheet (Control group)

(iii) Consent form

(iv) Debrief sheet

G Data

(i) ANOVA results

(ii) ANCOVA results

(iii) Skewness and kurtosis data

H Journal of Anxiety Disorders: Publication Guidelines for Authors

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Appendix A: Poster advertisements

(i) Clinical OCD group

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(ii) Control group

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Appendix B: Favourable ethical opinion

(i) University if Surrey ethics committee

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(ii) NHS National Health Research Authority – NRES South Coast, Surrey

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Appendix C: Measures (Part 1)

(i). Demographics

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(ii) NART

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(iii) MINI

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N.B due to file size only the cover page has been inserted in the document.

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(iv) MMSE

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(v) OCIR

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(vi) PHQ9

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(vii) STAI – Trait anxiety

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Appendix D: Measures (Part 2)

(i) STAI – State anxiety

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(ii) Visual Analogue scale for memory confidence

(this was presented on the computer screen)

How confident are you that you heard this word before?

1----------------------------------------------------------10

Not confident very confident At all

(Note: All numbers between 0 and 10 were visible, and participants selected whole numbers)

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Appendix E: Stimuli

Stimuli validation

Nonverbal (pictures) and verbal (words) stimuli were piloted prior to experimental

use and rated by clinicians with OCD expertise for valence; their relevance to OCD checking

and contamination behaviour; concreteness and imaginability (words only).

(i) Nonverbal stimuli selection including examples

Nonverbal stimuli (pictures) taken from the IAPS database (Lang, Bradley & Cuthbert,

2005) or from the Google search engine were used. The IAPS database contains valence

ratings for a variety of images. Five clinicians with OCD expertise were asked to rate 134

images for OCD checking relevance (M = 7.45), OCD contamination relevance (M = 4.53),

positive valence (M = 3.60) and negative valence (M = 5.97).. As the neutral items were

chosen based on neutral semantic categories, there was not sufficient time for these items to

be controlled in the same way as the nonverbal OCD-relevant items were.

In the study phase a pool 25 images were identified: 20 neutral images and 5 OCD

checking-relevant images (referred to as OCD-relevant stimuli in the text). In the recognition

phase 50 images were identified: 40 neutral and 10 OCD-relevant items. Images were

considered OCD-relevant if they were rated between 1-3 for negative valence, as well as

rated between 7-10 for checking relevance (same as words).

Stimuli examples:

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Neutral:

OCD-relevant:

Table E1.

Stimuli means for OCD-relevant nonverbal items used in stimulus validation

Image

OCD CC

relevance

M

OCD Con*

relevance

M

Valence

Positive

M

Valence

Negative

M

Bath full 7.00 5.00 4.00 5.00

Boiling pot 8.00 2.25 3.33 6.33

Bolt 7.00 4.25 3.67 5.67

Broken wire 1 8.25 3.25 2.33 8.00

Broken wire 2 8.25 4.25 2.00 8.00

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Candle 1 7.00 2.75 7.33 3.33

Candle 3 7.25 5.00 3.33 5.67

Car 1 7.25 3.50 3.67 5.33

Car mirror 1 7.00 1.75 4.00 5.67

Check light 7.75 3.25 3.67 5.00

Cigarette 2 8.00 6.00 2.00 7.00

Door latch 1 7.25 4.75 3.00 5.67

Door latch 2 7.50 3.75 4.67 5.67

Door lock 1 8.00 3.25 3.33 7.33

Door open 2 7.00 3.00 3.67 5.00

Door open 3 7.00 2.50 3.67 5.67

Electric hob on 7.75 2.50 3.67 6.67

Electric socket 1 8.75 3.50 2.33 7.33

Electric socket 2 8.00 5.25 3.33 6.67

Electric socket 3 7.75 3.25 3.00 6.67

Gas fire 7.75 4.00 5.00 6.33

Gas hob on 7.25 1.75 4.00 5.33

Hair dryer on 7.25 4.25 3.33 6.00

Iron on 1 8.25 3.00 3.67 6.00

Iron on 2 8.00 2.75 4.67 6.00

Kettle on 7.25 2.50 5.00 4.33

Knife 7.00 5.50 3.00 6.33

Light switch 1 7.00 3.75 3.33 4.33

Light switch 2 7.50 3.75 3.67 4.67

Log fire 8.00 4.75 6.00 5.33

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Medication 1 7.25 3.50 3.00 6.67

Mouse fire 7.75 3.00 3.00 7.00

Overflow 1 8.00 4.75 3.33 7.00

Overflow 2 8.00 4.50 3.00 7.67

Padlock closed 7.25 5.75 4.00 5.00

pot on 7.75 2.00 5.33 4.33

Straighteners 1 8.50 2.75 4.33 6.67

Straighteners 2 8.50 3.00 4.00 4.67

Tap on 1 7.75 5.25 5.67 3.67

Tap on 3 7.50 6.00 4.33 5.33

Toaster on 8.25 4.50 5.00 5.33

Window open 1 9.00 2.00 3.00 7.00

Window open 2 7.00 2.00 6.00 4.00

Window open 3 7.25 2.50 4.00 5.00

Light switch 2 8.25 5.25 4.33 5.67

Note: *Con = Contamination

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(ii) Verbal stimuli selection including examples

A pool of 10 OCD-relevant words, controlled for word length (M = 4.80), valence (M

= 3.30), frequency (M = 54.80 ), concreteness (M = 3.61), Imaginability (M = 4.26) and OCD

checking relevance (M = 9.06 ) were taken from Bradley & Lang (1999) and Richards et al.,

(in preparation) were used. As the neutral items were chosen based on neutral semantic

categories, there was not sufficient time for these items to be controlled in the same way as

the verbal OCD-relevant items were.

In the study phase a pool of 25 words were used: twenty neutral (linked to four neutral

categories) and five OCD-relevant words. During the recognition phase a pool of fifty words

were used: 40 neutral (linked to four neutral categories) and 10 OCD-relevant words. Words

were considered OCD-relevant if they were rated between 1-3 for negative valence, as well

as rated between 7-10 for checking relevance (same as pictures).

Stimuli examples:

Neutral:

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OCD-relevant:

Wardrobe

Lawyer

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Table E2.

Stimuli means for OCD-relevant verbal items used in stimulus validation

Word Valence

M

Frequency

M

No. of

Letters

Concreteness

M

Imaginability

M

OCD CC

Relevance

M

Peril 2.55 34 5 2.55 4.73 8.16

Fire 4.73 187 4 9.27 9.55 8.75

Risk 3.82 54 4 2.55 2.18 9.33

Fault 3.64 22 5 2.09 1.82 9.5

Forget 4.18 62 5 3.18 2.91 9.66

Blame 2.45 34 5 2.18 2.36 8.33

Harm 2.91 25 4 2.91 4.00 9.50

Ruin 3.45 31 4 4.91 5.64 8.5

Scared 2.82 52 6 3.18 5.09 9.5

Harm

Blame

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Infect 2.40 47 6 3.30 4.30 9.33

Unsafe 2.91 25 4 2.91 4.00 9.5

Murder 1.73 75 6 5.36 7.18 9.5

Worry 3.27 78 5 3.36 3.73 9.33

Doubt 3.82 40 5 3.55 3.45 9

Fatal 1.73 38 5 3.36 4.64 8.5

Panic 1.91 22 5 3.82 4.55 9

Lethal 2.00 32 6 3.18 2.91 8.66

Danger 3.18 70 6 3.45 4.55 9

Guilty 2.45 68 6 2.82 3.09 9.5

Fret 3.45 28 4 4.00 4.09 9.33

Ajar 5.00 25 4 4.36 7.09 8.33

Burnt 3.36 24 5 6.45 7.73 7

Cancer 1.09 25 6 7.18 6.27 8.66

Flood 2.55 19 5 7.36 8.82 8.5

Error 3.82 36 5 3.0 2.91 9

Check 4.00 27 5 4.00 3.00 9

Burning 2.25 59 7 7.25 8.50 8.25

Scald 1.75 31 5 7.50 8.00 6.5

Hazard 2.75 12 6 4.25 3.75 6.75

Plug 4.50 23 4 9.00 9.50 8.00

Switch 4.50 13 6 9.00 9.50 8.00

Sharp 3.50 26 5 4.25 6.25 7.5

Blade 3.75 13 5 8.50 8.75 6.75

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Ablaze 2.25 21 6 5.25 7.50 7.75

Crash 2.00 31 5 4.75 6.25 7.25

Knife 3.25 76 5 8.75 9.00 8.00

Needle 3.50 15 6 8.00 9.00 7.00

Threat 2.00 42 6 3.503.00 3.00 6.50

anxious 3.00 17 7 2.505.00 5.00 6.50

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(iii) Filler task examples

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Appendix F: Participant Forms

(i) Information sheet (Clinical OCD group)

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(ii) Participant Information Sheet (Control group)

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(iii) Consent form

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(iv) Debrief sheet

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Appendix G Data

(i) ANOVA results

F df p η2

Recall – Accuracy

Material 43.08 1, 32 <.001 .57

Material x Group 1.21 1, 32 .281 .04

Time 37.93 1, 32 <.001 .54

Time x Group .49 1, 32 .499 .01

Material x Time 3.96 1, 32 .055 .11

Material x Time x Group 2.94 1, 32 .096 .08

Group 1.84 1, 32 .185 .05

Recall – Organisational strategy (Total)

Material 29.03 1, 32 <.001 .48

Material x Group 2.85 1, 32 .101 .48

Time .08 1, 32 .932 .00

Time x Group .08 1, 32 .932 .00

Material x Time .06 1, 32 .814 .00

Material x Time x Group .06 1, 32 .814 .00

Group .46 1, 32 .504 .01

Recall – Organisational strategy

(categorisation)

Material 34.86 1, 32 <.001 .52

Material x Group 3.23 1, 32 .082 .09

Time .05 1, 32 .826 .00

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Time x Group .10 1, 32 .759 .00

Material x Time .33 1, 32 .569 .01


Group .38 1, 32 .541 .01


(presentation order)

Material 1.76 1, 32 .194 .05

Material x Group .07 1, 32 .792 .00

Time 1.35 1, 32 .253 .04

Time x Group .15 1, 32 .70 .00

Material x Time 2.15 1, 32 .153 .06

Material x Time x Group 1.44 1, 32 .239 .04

Group .41 1, 32 .526 .01

Recall – Repetitions

Material 2.71 1, 32 .110 .08


Time .418 1, 32 .049 .12

Time x Group .09 1, 32 .772 .00

Material x Time .08 1, 32 .78 .00


Group .42 1, 32 .523 .01

Recall – Intrusions

Material 2.92 1, 32 .097 .08


Time .46 1, 32 .505 .01

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Time x Group .46 1, 32 .505 .01

Material x Time 1.67 1, 32 .206 .05

Material x Time x Group .00 1, 32 1.00 .00

Group 1.96 1, 32 .171 .06

Recognition - Hits

Material 30.38 1, 32 <.001 .49

Material x Group .075 1, 32 .786 .00

Category 2.30 1, 32 .139 .07

Category x Group 1.49 1, 32 .231 .05

Material x Category 2.86 1, 32 .101 .08

Material x Category x Group .13 1, 32 .718 .00

Group 1.23 1, 32 .275 .04

Recognition – False alarms

Material 37.31 1, 32 <.001 .54


Category 10.16 1, 32 .003 .24

Category x Group .81 1, 32 .375 .03

Material x Category .01 1, 32 .925 .00


Group .68 1, 32 .416 .02

Recognition – d’ prime

Material 72.43 1, 32 <.001 .69


Category 14.09 1, 32 .001 .31




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Group 1.66 1, 32 .207 .05

Metamemory – Response bias (C)

Material .07 1, 32 .795 .00

Material x Group .003 1, 32 .954 .00

Category 8.09 1, 32 .008 .20

Category x Group 2.09 1, 32 .158 .06



Group .21 1, 32 .654 .01

Metamemory - Confidence

Material 42.11 1, 32 <.001 .57


Category .00 1, 32 .963 .00

Category x Group 1.32 1, 32 .258 .04

List type 71.41 1, 32 <.001 .69

List type x Group 1.04 1, 32 .315 .03


Material x Category x Group 2.33 1, 32 .137 .07

Material x List type .37 1, 32 .545 .01

Material x List type x Group 1.43 1, 32 .241 .04

Category x List type 3.33 1, 32 .077 .09

Category x List type x Group .46 1, 32 .501 .01

Material x Category x List type 1.44 1, 32 .239 .04

Material x Category x List type x

Group

2.34 1, 32 .136 .07

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Group 4.37 1, 32 .045 .12

Metamemory – familiarity (Remember,

Know, Guess)

Material 5.56 1, 32 .025 .15


Category .19 1, 32 .665 .01


Judgement 123.03 2, 64 <.001 .79

Judgement x Group 2.17 2, 64 .138 .06



Material x Judgement 13.16 2, 64 <.001 .29

Material x Judgement x Group .70 2, 64 .477 .02

Category x Judgement .27 2, 64 .703 .01

Category x Judgement x Group .34 2, 64 .654 .01

Material x Category x Judgement .64 2, 64 .474 .02

Material x Category x Judgement

x Group

.13 2, 64 .801 .00

Group .22 1, 32 .641 .01

Metamemory – familiarity (Remember

Vs. Know)

Material 36.28 1, 32 <.001 .53


Category 1.54 1, 32 .224 .05

Category x Group 1.54 1, 32 .224 .05

Judgement 95.40 1, 32 <.001 .75

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Material x Judgement 16.92 1, 32 <.001 .35

Material x Judgement x Group 1.68 1, 32 .205 .05



Material x Category x Judgement .49 1, 32 .491 .02


x Group

.08 1, 32 .785 .00

Group 2.65 1, 32 .113 .08

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(ii) ANCOVA results

F df p η2

Recall – Accuracy

Material 4.69 1, 31 .038 .13

Material x STAI_Total .60 1, 31 .443 .02

Material x Group 1.79 1, 31 .191 .05

Time .01 1, 31 .926 .00

Time x STAI_Total 1.63 1, 31 .210 .05

Time x Group .08 1, 31 .786 .00

Material x Time 3.18 1, 31 .084 .09

Material x Time x STAI_Total 5.26 1, 31 .029 .15


Group .15 1, 31 .703 .01

STAI_Total 1.11 1, 31 .300 .41

Recall – Organisational strategy (total)

Material 5.64 1, 31 .024 .15

Material x STAI_Total 1.52 1, 31 .228 .05

Material x Group 4.39 1, 31 .044 .12

Time .03 1, 31 .864 .00

Time x STAI_Total .03 1, 31 .875 .00

Time x Group .03 1, 31 .869 .00

Material x Time .21 1, 31 .647 .01

Material x Time x STAI_Total .28 1, 31 .602 .01


Group .18 1, 31 .678 .01

STAI_Total 2.27 1, 31 .142 .07


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(Categorisation)

Material 6.02 1, 31 .019 .16

Material x STAI_Total 1.47 1, 31 .234 .05

Material x Group 4.71 1, 31 .038 .13

Time .08 1, 31 .781 .00

Time x STAI_Total .06 1, 31 .812 .00

Time x Group .01 1, 31 .933 .00

Material x Time .13 1, 31 .723 .00

Material x Time x STAI_Total .24 1, 31 .626 .01


Group .21 1, 31 .650 .01

STAI_Total 2.23 1, 31 .145 .06

Metamemory - Confidence

Material .23 1, 31 .632 .01



Category .00 1, 31 1.00 .00

Category x STAI_Total .00 1, 31 .99 .00


ListType .61 1, 31 .441 .02

ListType x STAI_Total 8.23 1, 31 .01 .21

ListType x Group .89 1, 31 .354 .03


Material x Category x

STAI_Total

2.33 1, 31 .137 .07

Material x Category x Group 4.72 1, 31 .038 .13

Material x ListType .43 1, 31 .518 .01

Material x ListType x

STAI_Total

.65 1, 31 .428 .02

Material x ListType x Group .17 1, 31 .684 .01111


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Category x ListType 4.77 1, 31 .037 .13

Category x ListType x

STAI_Total

3.31 1, 31 .079 .10

Category x ListType x Group 2.89 1, 31 .100 .09

Material x Category x ListType 2.13 1, 31 .155 .06

Material x Category x ListType x

STAI_Total

1.51 1, 31 .229 .05

Material x Category x ListType x

Group

.18 1, 31 .679 .01

Group .59 1, 31 .450 .02

STAI_Total 1.92 1, 31 .176 .06

Metamemory – familiarity (Remember

Vs. Know)

Material 4.76 1, 31 .037 .13



Category 4.08 1, 31 .052 .12

Category x STAI_Total 3.19 1, 31 .084 .09

Category x Group 4.50 1, 31 .042 .13

Judgement 1.64 1, 31 .210 0.5

Judgement x STAI_Total .70 1, 31 .409 .02



Material x Category x

STAI_Total

.94 1, 31 .341 .03


Material x Judgement .00 1, 31 .981 .00

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Material x Judgement x

STAI_Total

.78 1, 31 .985 .02

Material x Judgement x Group 2.42 1, 31 .130 .07


Category x Judgement x

STAI_Total

.11 1, 31 .745 .00


Material x Category x Judgement 3.93 1, 31 .056 .11


x STAI_Total

4.81 1, 31 .036 .13


x Group

2.60 1, 31 .117 .08

Group 4.56 1, 31 .040 .13

STAI_Total 1.87 1, 31 .182 .06

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(iii) Skewness and Kurtosis

Clinical OCD Variable

Skewness Z

Kurtosis Z

Control Variable

Skewness Z

Kurtosis Z

age 0.40 -0.62 age 2.49 1.26Age left School

0.00 -2.07Age left School

-0.97 -1.76OCI-R Total 1.21 -0.48 OCI-R Total -0.86 -0.19Check 1.21 -0.09 Check 1.15 -0.54Wash -0.04 -1.54 Wash 1.43 -0.63Hoard 2.32 2.14 Hoard 2.25 0.80Neutralise 0.59 -1.18 Neutralise 2.96 2.41Obsess -1.47 -0.69 Obsess 2.32 1.21Order 0.97 -0.80 Order 0.37 -0.91PHQ-9 1.06 0.40 PHQ-9 1.10 -0.01FSIQ -0.74 -0.86 FSIQ 1.27 0.22MMSE -2.49 -0.14 MMSE -1.88 -0.08STAI-T 0.18 0.08 STAI-T 0.96 -0.25STAI-S 1 1.40 0.70 STAI-S 1 1.24 0.22STAI-S 2 1.35 0.39 STAI-S 2 1.21 0.78STAI-S 3 0.49 -0.80 STAI-S 3 0.30 0.01STAI-S 4 2.08 0.90 STAI-S 4 0.28 -0.83STAI-P1 1.59 0.55 STAI-P1 0.74 -0.06STAI-P2 1.26 1.64 STAI-P2 1.30 0.51STAI-W1 -0.11 -0.62 STAI-W1 0.50 0.32STAI-W2 1.70 -0.03 STAI-W2 0.05 -0.59Verb-Imm-Acc -0.23 0.74 Verb-Imm-Acc 1.87 0.30Verb-Imm-Org 1.40 -0.66 Verb-Imm-Org 1.77 -0.46Verb-Imm-Org-Cat

1.44 -0.69Verb-Imm-Org-Cat

2.13 0.37Verb-Imm-Org-Pres

2.99 2.49Verb-Imm-Org-Pres

3.16 2.35Verb-Imm-Repetition 4.50 5.49

Verb-Imm-Repetition 5.85 10.62

Verb-Imm-Intrusion5.86 10.64

Verb-Imm-Intrusion1.81 -1.10

Verb-Del-Acc -0.51 -0.67 Verb-Del-Acc 1.97 0.15Verb-Del-Org 1.36 0.13 Verb-Del-Org 1.25 -0.82Verb-Del-Org-Categ 1.82 0.52

Verb-Del-Org-Categ 1.49 -0.52

Verb-Del-Org-Pres3.92 5.33

Verb-Del-Org-Pres3.63 5.36

Verb-Del-Repetition 7.50 15.99

Verb-Del-Repetition 4.75 5.12

Verb-Del-Intrusion3.71 3.69

Verb-Del-Intrusion3.58 4.59

Pic-Imm-Acc 0.18 -0.50 Pic-Imm-Acc -0.36 -1.17

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Pic-Imm-Org -0.03 -0.59 Pic-Imm-Org 1.04 0.15Pic-Imm-Org-Categ

-0.07 -0.52Pic-Imm-Org-Categ

1.08 0.48Pic-Imm-Ord-Pres

1.36 -0.21Pic-Imm-Ord-Pres

0.29 -0.63Pic-Imm-Repetition

2.30 0.37Pic-Imm-Repetition

3.05 1.72Pic-Imm-Intrusion

2.68 2.10Pic-Imm-Intrusion

4.75 5.12Pic-Del-Acc 0.33 -0.06 Pic-Del-Acc 1.23 -0.61Pic-Del-Org -0.06 -0.75 Pic-Del-Org 1.94 0.26Pic-Del-Org-Categ

0.10 -0.50Pic-Del-Org-Categ

1.97 0.33Pic-Del-Org-Pres

2.77 1.03Pic-Del-Org-Pres

0.72 -1.98Pic-Del-Repetition

3.61 3.24Pic-Del-Repetition

3.32 1.95Pic-Del-Intrusion

5.13 8.72Pic-Del-Intrusion

4.75 5.12P_H_OCD_s -2.30 0.37 P_H_OCD_s -3.39 1.57P_H_A_s -5.28 8.10 P_H_A_s -2.49 -0.14P_H_M_s -2.90 1.79 P_H_M_s -2.49 -0.14P_H_V_s -1.50 -0.38 P_H_V_s -3.39 1.57P_H_T_s -2.90 1.79 P_H_T_s -2.86 0.91P_FA_OCD_n 4.07 4.30 P_FA_OCD_n 1.23 -1.66P_FA_A_n 1.82 -0.39 P_FA_A_nP_FA_M_n 0.20 -1.38 P_FA_M_n 1.43 -0.08P_FA_V_n 2.76 1.40 P_FA_V_n 2.37 0.73P_FA_T_n 2.07 -0.29 P_FA_T_n 3.61 3.24P_C_OCD_s -3.15 2.64 P_C_OCD_s -3.39 3.10P_C_A_s -4.74 7.20 P_C_A_s -2.87 3.71P_C_M_s -3.22 2.44 P_C_M_s -1.82 -0.16P_C_V_s -1.87 1.21 P_C_V_s -2.91 1.84P_C_T_s -2.91 2.57 P_C_T_s -2.80 1.77P_C_OCD_n -1.52 0.30 P_C_OCD_n -2.17 0.75P_C_A_n . . P_C_A_n . .P_C_M_n -0.52 -1.14 P_C_M_n -1.79 2.03P_C_V_n -1.55 -0.66 P_C_V_n -1.04 -0.44P_C_T_n -0.88 -0.83 P_C_T_n -0.23 -0.91P_R_OCD_s -1.79 -0.06 P_R_OCD_s -2.46 1.02P_R_A_s -0.93 -0.88 P_R_A_s 0.47 0.69P_R_M_s -1.19 -0.80 P_R_M_s -1.61 -0.10P_R_V_s -0.75 -0.50 P_R_V_s -0.47 -2.00P_R_T_s -1.57 0.76 P_R_T_s -0.12 -1.12P_R_OCD_n 3.39 1.57 P_R_OCD_n 4.75 5.12P_R_A_n 7.50 15.99 P_R_A_n 7.50 15.99P_R_M_n 2.32 0.83 P_R_M_n 3.39 1.57P_R_V_n 4.75 5.12 P_R_V_n 5.70 9.21

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P_R_T_n

5.70 9.21

P_R_T_n

7.50

15.99

P_K_OCD_s 3.31 3.43 P_K_OCD_s 3.97 5.32P_K_A_s 1.26 -1.16 P_K_A_s -0.72 -1.98P_K_M_s 2.85 1.51 P_K_M_s 1.88 -0.08P_K_V_s 1.81 0.72 P_K_V_s 1.22 -1.46P_K_T_s 2.96 3.68 P_K_T_s 1.81 -0.05P_K_OCD_n 4.50 5.49 P_K_OCD_n 3.39 1.57P_K_A_n 3.34 2.54 P_K_A_n 2.49 -0.14P_K_M_n 1.50 -0.38 P_K_M_n 2.30 0.37P_K_V_n 2.73 1.42 P_K_V_n 3.61 3.24P_K_T_n 5.70 9.21 P_K_T_n 3.39 1.57P_G_OCD_s 3.39 1.57 P_G_OCD_s . .P_G_A_s 7.50 15.99 P_G_A_s . .P_G_M_s 5.70 9.21 P_G_M_s 7.50 15.99P_G_V_s 3.39 1.57 P_G_V_s . .P_G_T_s 7.50 15.99 P_G_T_s . .P_G_OCD_n 7.50 15.99 P_G_OCD_n 7.50 15.99P_G_A_n 2.49 -0.14 P_G_A_n 4.75 5.12P_G_M_n 2.77 1.03 P_G_M_n 2.49 -0.14P_G_V_n . . P_G_V_n 3.61 3.24P_G_T_n 3.39 1.57 P_G_T_n 7.50 15.99P_N_OCD_s 2.30 0.37 P_N_OCD_s 3.39 1.57P_N_A_s 5.28 8.10 P_N_A_s 2.49 -0.14P_N_M_s 2.90 1.79 P_N_M_s 3.39 1.57P_N_V_s 1.50 -0.38 P_N_V_s 3.39 1.57P_N_T_s 2.90 1.79 P_N_T_s 3.40 2.25P_N_OCD_n -3.95 3.44 P_N_OCD_n -1.81 0.19P_N_A_n -1.82 -0.39 P_N_A_n -3.93 4.41P_N_M_n -0.20 -1.38 P_N_M_n -1.65 -0.08P_N_V_n -2.76 1.40 P_N_V_n -2.37 0.73P_N_T_n -2.07 -0.29 P_N_T_n -4.99 7.75W_H_OCD_s -0.97 -0.58 W_H_OCD_s -0.53 -1.13W_H_A_s -1.81 0.72 W_H_A_s -1.61 0.57W_H_M_s -2.21 0.82 W_H_M_s -0.90 -1.28W_H_V_s -1.09 -0.18 W_H_V_s -1.54 -0.30W_H_T_s -0.53 -1.13 W_H_T_s -4.46 7.45W_FA_OCD_n

0.76 -0.73W_FA_OCD_n

1.09 -0.18W_FA_A_n 0.85 -0.92 W_FA_A_n -0.13 -1.27W_FA_M_n 1.15 0.51 W_FA_M_n 0.27 -1.56W_FA_V_n 0.23 0.40 W_FA_V_n 1.15 -0.12W_FA_T_n 1.24 -0.95 W_FA_T_n 1.43 -0.47W_C_OCD_s -2.74 3.28 W_C_OCD_s -0.66 -0.86

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W_C_A_s

-1.63 0.93

W_C_A_s

0.56

-1.02

W_C_M_s -1.91 0.30 W_C_M_s -1.71 0.81W_C_V_s -0.37 -0.55 W_C_V_s 0.09 -0.99W_C_T_s -0.11 -0.34 W_C_T_s -1.33 -0.41W_C_OCD_n -1.37 0.25 W_C_OCD_n 0.63 -0.70W_C_A_n -3.53 3.92 W_C_A_n -0.02 -0.72W_C_M_n -1.17 0.26 W_C_M_n 0.22 -1.24W_C_V_n -1.84 0.44 W_C_V_n 0.67 -0.69W_C_T_n -0.68 -0.75 W_C_T_n 0.26 -0.76W_R_OCD_s 0.68 -0.35 W_R_OCD_s 0.16 -1.38W_R_A_s 0.75 -0.46 W_R_A_s 0.84 -0.45W_R_M_s -0.69 -0.60 W_R_M_s 0.79 -0.91W_R_V_s 0.13 -0.84 W_R_V_s 0.51 -0.92W_R_T_s 0.25 -0.95 W_R_T_s 0.80 -1.08W_R_OCD_n 4.75 5.12 W_R_OCD_n 4.75 5.12W_R_A_n 2.90 1.79 W_R_A_n 7.50 15.99W_R_M_n 4.75 5.12 W_R_M_n 5.70 9.21W_R_V_n 2.90 1.79 W_R_V_n 2.30 0.37W_R_T_n 3.39 1.57 W_R_T_n 2.49 -0.14W_K_OCD_s 1.58 1.03 W_K_OCD_s 2.63 2.48W_K_A_s 0.90 -1.03 W_K_A_s 1.81 -0.33W_K_M_s 2.63 2.48 W_K_M_s 1.88 -0.08W_K_V_s 0.39 -0.76 W_K_V_s 1.45 -0.20W_K_T_s 2.00 0.72 W_K_T_s 0.50 -0.73W_K_OCD_n 2.30 0.37 W_K_OCD_n 2.68 2.10W_K_A_n 1.59 -0.36 W_K_A_n 0.73 -0.53W_K_M_n 1.50 -0.38 W_K_M_n 2.37 0.73W_K_V_n 0.83 -0.57 W_K_V_n 1.08 -0.92W_K_T_n 1.65 -0.08 W_K_T_n 2.24 0.52W_G_OCD_s 2.46 0.15 W_G_OCD_s 2.90 1.79W_G_A_s 2.21 0.82 W_G_A_s 3.97 5.32W_G_M_s 3.32 1.95 W_G_M_s 3.61 3.24W_G_V_s 2.30 0.37 W_G_V_s 2.90 1.79W_G_T_s 2.30 0.37 W_G_T_s 3.65 3.48W_G_OCD_n 1.50 -0.38 W_G_OCD_n 2.77 1.03W_G_A_n 0.83 -0.57 W_G_A_n 2.74 1.31W_G_M_n 2.90 1.79 W_G_M_n 1.71 -0.61W_G_V_n 0.40 -1.17 W_G_V_n 4.50 5.49W_G_T_n 2.32 0.83 W_G_T_n 3.39 1.57W_N_OCD_s 0.97 -0.58 W_N_OCD_s 0.53 -1.13W_N_A_s 1.81 0.72 W_N_A_s 1.61 0.57W_N_M_s 2.21 0.82 W_N_M_s 0.90 -1.28

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W_N_V_s 1.09 -0.18 W_N_V_s 1.54

-0.30

W_N_T_s 0.53 -1.13 W_N_T_s 4.46 7.45W_N_OCD_n -0.76 -0.73 W_N_OCD_n -1.09 -0.18W_N_A_n -0.85 -0.92 W_N_A_n 0.13 -1.27W_N_M_n -1.15 0.51 W_N_M_n -0.27 -1.56W_N_V_n -0.23 0.40 W_N_V_n -1.15 -0.12W_N_T_n -1.24 -0.95 W_N_T_n -1.43 -0.47P_H_Neu_s -3.58 4.00 P_H_Neu_s -2.48 0.77P_FA_Neu_n 1.32 -0.60 P_FA_Neu_n 1.70 -0.34P_C_Neu_s -2.60 2.06 P_C_Neu_s -3.75 4.71P_R_Neu_s -0.56 -1.18 P_R_Neu_s -1.14 -0.45P_K_Neu_s 2.14 0.30 P_K_Neu_s 1.09 -0.62P_G_Neu_s 2.46 0.15 P_G_Neu_s 7.50 15.99P_N_Neu_s 3.58 4.00 P_N_Neu_s 3.10 2.03P_C_Neu_n -1.01 -1.04 P_C_Neu_n -0.65 -0.49P_R_Neu_n 5.55 9.62 P_R_Neu_n 3.65 3.48P_K_Neu_n 2.90 1.98 P_K_Neu_n 2.00 0.16P_G_Neu_n 3.26 2.25 P_G_Neu_n 2.04 0.07P_N_Neu_n -1.32 -0.60 P_N_Neu_n -3.05 2.61W_H_Neu_s -0.17 -0.59 W_H_Neu_s -0.75 -0.81W_FA_Neu_n 0.68 0.46 W_FA_Neu_n -0.45 -1.14W_C_Neu_s -0.54 0.95 W_C_Neu_s 0.22 -1.18W_R_Neu_s 0.51 -0.28 W_R_Neu_s 0.85 -0.49W_K_Neu_s 2.97 3.52 W_K_Neu_s 1.29 0.51W_G_Neu_s 2.03 0.47 W_G_Neu_s 4.16 5.38W_N_Neu_s 0.17 -0.59 W_N_Neu_s 0.75 -0.81W_C_Neu_n -1.89 0.92 W_C_Neu_n 0.47 -1.08W_R_Neu_n 2.40 1.36 W_R_Neu_n 1.58 -0.79W_K_Neu_n 0.56 -0.73 W_K_Neu_n 0.59 -0.60W_G_Neu_n 0.75 -1.08 W_G_Neu_n 1.30 -0.94W_N_Neu_n -0.68 0.46 W_N_Neu_n 0.45 -1.14P_C_OCD_SN -2.83 2.37 P_C_OCD_SN -1.67 0.69P_C_Neu_SN -1.37 -0.76 P_C_Neu_SN -0.97 -0.21W_C_OCD_SN -2.93 3.54 W_C_OCD_SN 0.55 -1.01W_C_Neu_SN -2.09 1.02 W_C_Neu_SN 0.69 -1.24P_C_OCDNEU_s -2.31 1.00 P_C_OCDNEU_s -1.85 0.27P_C_OCDNEU_n -1.63 -0.28 P_C_OCDNEU_n -1.41 0.36W_C_OCDNEU_s -1.91 1.74 W_C_OCDNEU_s -0.13 -1.22W_C_OCDNEU_n -1.65 0.81 W_C_OCDNEU_n 0.59 -0.97P_OCD_dp -2.63 2.06 P_OCD_dp -1.38 -0.18P_Neutr_dp -0.39 -1.20 P_Neutr_dp -0.45 -0.40W_OCD_dp 0.38 0.34 W_OCD_dp -0.75 -0.81

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W_Neutr_dp 0.50 -0.45 W_Neutr_dp 0.63 -0.25P_OCD_cp -0.15 0.71 P_OCD_cp 0.26 -0.22P_Neutr_cp 0.58 -1.15 P_Neutr_cp 0.62 -0.18W_OCD_cp 0.65 -0.82 W_OCD_cp 0.33 -1.02W_Neutr_cp -0.69 0.34 W_Neutr_cp -0.29 -1.18P_R_percent_OCD_s -2.34 0.42

P_R_percent_OCD_s -3.55 4.08

P_R_percent_Neu_s -1.53 -0.65 P_R_percent_Neu_s -1.35 -0.29P_K_percent_OCD_s 2.99 1.89

P_K_percent_OCD_s 3.55 4.08

P_K_percent_Neu_s 2.00 0.13

P_K_percent_Neu_s 1.04 -0.76

P_G_percent_OCD_s 3.51 1.96

P_G_percent_OCD_s . .

P_G_percent_Neu_s 2.53 0.31

P_G_percent_Neu_s 7.50 15.99

W_R_percent_OCD_s -0.64 -0.54

W_R_percent_OCD_s -0.77 -0.37

W_R_percent_Neu_s -0.31 -0.72

W_R_percent_Neu_s -0.69 -0.94

W_K_percent_OCD_s 1.71 0.36

W_K_percent_OCD_s 1.90 0.52

W_K_percent_Neu_s 2.22 1.39

W_K_percent_Neu_s 0.20 -0.13

W_G_percent_OCD_s 3.99 4.78

W_G_percent_OCD_s 3.21 2.16

W_G_percent_Neu_s 1.67 -0.35

W_G_percent_Neu_s 4.13 5.50

STAI_S_Total 1.51 0.39 STAI_S_Total 0.43 -0.08VerbOrg 1.57 -0.26 VerbOrg 1.54 -0.76PicOrg -0.17 -0.70 PicOrg 2.23 0.89VerbOrgCateg 1.70 -0.23 VerbOrgCateg 1.72 -0.40PicOrgCateg -0.21 -0.71 PicOrgCateg 2.27 1.08P_R_percent_OCDNeu_s -2.36 0.46

P_R_percent_OCDNeu_s -2.63 2.31

P_K_percent_OCDNeu_s 2.99 1.80

P_K_percent_OCDNeu_s 2.70 2.62

P_G_percent_OCDNeu_s 2.83 0.86

P_G_percent_OCDNeu_s 7.50 15.99

W_R_percent_OCDNeu_s -0.08 -1.07

W_R_percent_OCDNeu_s -0.49 -0.78

W_K_percent_OCDNeu_s 1.63 -0.05

W_K_percent_OCDNeu_s 1.51 0.28

W_G_percent_OCDNeu_s 3.15 2.46

W_G_percent_OCDNeu_s 4.17 5.13

P_KG_percent_OCDNeu_s 2.36 0.46

P_KG_percent_OCDNeu_s 2.63 2.31

W_KG_percent_OCDNeu_s 0.08 -1.07

W_KG_percent_OCDNeu_s 0.49 -0.78

Conf_PW_OCD_s -3.61 5.02 Conf_PW_OCD_s -0.48 -0.76119


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Conf_PW_OCD_n -0.91 -0.58 Conf_PW_OCD_n 0.00 -0.96Conf_PW_Neu_s -1.56 -0.27 Conf_PW_Neu_s -0.13 -0.88Conf_PW_Neu_n -1.79 -0.21 Conf_PW_Neu_n 0.06 -0.78

After exploration of histograms, data were decided to be non-parametric if:

their skewness and kurtosis z scores were ≥ ± 2 (i.e. 2 SD from the mean),

and

there were a large number of unexplained outliers

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Appendix H: Journal of Anxiety Disorders - Publication guidance for authors

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Major Research Proposal

An investigation of verbal and nonverbal memory deficits in OCD whilst controlling for

spontaneous organisational strategy use and state anxiety

2998 Words

Year 1

August 2012

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Project Title: An investigation of verbal and nonverbal memory deficits in OCD whilst

controlling for spontaneous organisational strategy use and state anxiety.

Introduction

*Literature review (Chapter 1)

Obsessive Compulsive Disorder (OCD) is characterised by recurrent obsessions (intrusive

thoughts and/or images that cause significant distress) and/or compulsions (repetitive

behaviours or mental acts aimed at neutralising the obsession) that cause marked distress and

interfere with daily functioning (Diagnostic Statistical Manual of Mental Disorders 4th

Edition, American Psychiatric Association, 1994). The most commonly reported obsessions

involve fear of contamination or doubt about past action, which often lead to repetitive

cleaning or checking compulsions.

A number of theories have been proposed regarding both development and maintenance of

OCD, such as cognitive theories (e.g. Salkovskis, 1985) and learning theories (e.g. de Silva

and Rachman, 1992); however neuropsychological research has suggested people with OCD

have reduced cognitive performance in domains such as attention, memory and executive

functioning. Initial research into OCD and memory suggested a global memory deficit (Sher,

Frost and Otto, 1983). However, inconsistent research findings in relation to material type

questioned this hypothesis. Recent reviews hypothesise that memory deficits in OCD may be

secondary to executive dysfunction (Kuelz, Hohagen and Voderholzer, 2004), in particular

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impaired strategic processing abilities impact the ability to implement organisational

strategies during the encoding phase of memory (Olley, Malhi and Sachdev, 2007).

Research has mainly focused on nonverbal memory, as previous research has pointed to a

deficit with this stimulus material, rather than verbal memory. The Rey Osterrieth Complex

Figure test (RCFT; Rey, 1941) has been used extensively in OCD memory research as it

assesses memory accuracy and organisational strategy use. Fairly consistent findings have

been reported in support of a mediating role for reduced organisational strategy use on

memory performance in OCD samples when compared to nonclinical control samples

(Savage, Baer, Keuthen, Rauch and Jenike, 1998; Penades, Catalan, Andres, Salamero and

Gasto, 1998). However, Shin, Park, Kim and Lee (2004) question this hypothesis and instead

suggest a general nonverbal memory deficit.

Research into organisational strategy use and verbal memory has produced somewhat

supportive findings of an organisational deficit. Deckersbach, Savage, Reilly-Harrington,

Clark, Sachs and Rauch (2004) found support for the hypothesis that impaired organisational

strategy use during encoding mediates verbal memory impairment.

Research that has used a within-participant design to compare organisational strategy use in

verbal and nonverbal memory has produced mixed results. Savage, Deckersbach, Willhelm,

Rauch, Baer, Reid and Jenike (2000) found support for a mediating role in both verbal and

nonverbal memory performance, whereas Exner, Kohl, Zaudig, Langs, Lincoln and Rief

(2009) found that although verbal memory was impaired, this was not mediated by

organisational strategy use.

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The research studies briefly outlined here (both verbal and nonverbal) share limitations that

may explain these inconsistencies – small sample sizes, using different scoring methods (i.e.

of the RCFT), different task demands (i.e. implicit vs. explicit), lack of an anxious control

group, and failing to control for Axis 1 co-morbidities. Future research is warranted to

attempt to explain the inconsistencies in the literature.

An interesting limitation is whether organisational memory differences found are OCD-

specific or a function of state anxiety– that is during the research is there a temporary change

in the participants anxiety levels due to an external factor, such as being involved in memory

research. Indeed, the majority of studies have failed to include an anxious control group to

assess whether the reduced use of organisational strategies are related to state anxiety.

Further, more recent studies have looked at the impact of memory confidence, and suggest

that people with OCD may have reduced confidence in their memory abilities rather than

impaired memory per se. This would be an interesting additional measure to a piece of

research that addresses the impact of state anxiety on memory abilities.

Given this, the current piece of research aims to investigate whether organisational deficits

are OCD-specific or an effect of state anxiety, and whether these deficits are stimulus

material specific (verbal vs. nonverbal). The proposed research will add to the current body

of literature on OCD and memory and might hold treatment implications for people with

OCD.

Research Question

Are organisational memory deficits OCD-specific or primarily due to state anxiety?

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Main Hypotheses (for quantitative studies only)

1. OCD group will score significantly lower than the non-OCD control group on measures of

encoding strategy use, memory accuracy and memory confidence.

2. There will be a significant interaction between OCD group and material type (verbal or

nonverbal) for encoding strategy use, memory accuracy and memory confidence.

3. State anxiety will reduce the above effects.

Method

Participants

Two groups (an OCD and control group) with 32 participants each will take part in the

research. A G*Power calculation (Faul, Erdfelder, Buchner and Lang, 2009) indicated this

sample size to achieve power of 0.8 and a probability level of 0.05. This was for the main

effect of OCD group on organisational strategy use and was based on an effect size of d=0.73

from Deckersbach et al (2005).

Description of sample and Inclusion criteria

OCD group:

1. Minimum age: 18 years137


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2. Meet DSM-IV diagnostic criteria for OCD using the Mini International

Neuropsychiatric Interview (MINI; Sheehan, Lecrubier and Sheehan et al. 1998)

3. Score ≥21 on the Obsessive Compulsive Inventory Revised (OCI-R; Foa, Huppert,

Leiberg, Hajcak and Langner, et al. 2002)

4. Score >7 on checking subscale of the OCI-R

Control group:

1. Minimum age: 18 years

2. Score <21 on the OCI-R

3. Score <8 on checking subscale of the OCI-R

Exclusion criteria

OCD group:

1. Score >14 on The Patient Health Questionnaire-9 (PHQ-9; Kroenke, Spitzer and

Williams, 2001)

2. Any known (self-reported) neurological or psychiatric condition

3. Score <27 on the Mini Mental State Examination (MMSE)

Control group:

1. Meet diagnostic criteria for OCD (MINI interview)

2. Score >14 on PHQ-9

3. Any known (self-reported) neurological or psychiatric condition

4. MMSE score <27

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Where participants will be recruited from

OCD group:

1. Charities – OCD Action, OCD UK, Mind, Oakleaf charity

2. Conferences - OCD UK conference 2012

3. OCD support groups – OCD UK London, Obsessive Compulsive Anonymous

(Guildford), OCD group Surbiton

Control group:

1. University staff and students (matched for age and gender)

Expected response-rate and potential pool of eligible participants

Previous MRPs involving OCD have used similar recruitment methods and were successful

in recruiting the desired number of participants to achieve sufficient power (Loverseed,

2010). Refer to the Feasibility section for alternative recruitment plans.

Design

The independent variables of the study are Group (between-group: OCD vs. Control) and

Material (within group: Verbal vs. Nonverbal). The dependent variables are spontaneous

organisational strategy use, memory accuracy and memory confidence. State anxiety is a co-

variate. Proposed data analysis will be discussed later.

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Measures

National Adult Reading Test (NART; Nelson, 1982) – A reading task of 50 irregularly

pronounced words and is commonly used as a predictor of verbal IQ. The NART has high

test-retest and inter-rater reliability and correlates highly with other validated measures of IQ

(Crawford, Parker, Stewart, De Lacey, 1989).

MINI – A widely used tool to assess diagnostic status and is considered to be a valid

alternative to the Structured Clinical Interview for DSM-IV (Sheehan et al, 1997).

MMSE - A brief 30-item screening assessment of cognitive impairment. It assesses functions

such as attention, memory, orientation and language. Scores of <27 indicate a underlying

cognitive impairment.

OCI-R – An 18-item self-report measure of obsessive compulsive symptoms that yields an

overall score (range 0-72) and has six subscale scores for washing, checking, ordering,

obsessing, hoarding and neutralising. Scores >20 indicates a likely presence of OCD (Foa,

Huppert, Leiberg, Hajcak, Langer et al, 2002). It has good internal consistency, convergent

validity and test re-test reliability (Hajcak, Huppert, Simons and Foa, 2004).

PHQ-9 – A 9-item self-report measure that corresponds directly with DSM-IV criteria for

major depressive disorder. Each item is rated for severity on a 4-point scale in relation to

frequency of experiencing symptoms. Total scores range from 0 (no depression) to 27 (severe

depression). It has high validity and reliability (Cameron, Crawford, Lawton and Reid, 2008)

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Spielberger State Trait Anxiety Inventory (STAI; Spielberger, Gorsuch, Lushene, Vagg and

Jacobs, 1983) – A 40-item self-report measure of state and trait anxiety. Each component has

20 items. The STAI is commonly used in research and has high internal consistency and test-

retest reliability (Spielberger et al, 1983).

Verbal and non-verbal stimuli – These will primarily consist of words and pictures from pre-

existing databases, such as IAPS (Lang, Bradley and Cuthbert, 2008). The words and pictures

in IAPS are standardised and matched for a range of factors. E.g. the words are matched for

frequency, word length and negative valence to name but a few. The pictures are matched for

arousal and valence. The OCD-relevant material will be designed by the researcher (as part of

a bigger OCD research group within the department) and piloted in Autumn 2012 prior to

being included in the proposed research.

Procedure

Please refer to the step-by-step procedure below whilst reading the text to aid clarification..

1. Clinical interview – complete MINI, OCI-R, PHQ-9, NART

2. Complete STAI (state and trait)

3. Verbal memory/Nonverbal memory test

a. Presented with words via speakers/on computer screen

b. Immediate recall

c. Distraction task

d. Delayed recall (30 minutes)

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e. Recognition – ‘old, new’

f. Confidence (VAS)

g. Remember, Know, Guess

h. Complete STAI (state only)

4. Strategy use feedback from participants

Participants for the OCD group will be recruited from OCD charities and support groups. The

control group will be recruited from the University and from the general public. OCD

charities (OCD Action, OCD UK) will be contacted regarding recruitment and discuss the

possibility of advertising the project online. The researcher will attend local meetings to give

information to group members and each charity will be given a poster to display. All potential

participants will be given an information sheet and a consent form to complete prior to data

collection.

Participants will initially be contacted by telephone to discuss the research and to confirm or

disconfirm OCD diagnosis using the MINI. Those who meet diagnostic criteria for OCD will

be allocated to the OCD group and those who do not will be allocated to the control group.

The PHQ-9 will also be administered via the telephone and people who score ≥ 15 will not be

invited to participate in the research because severe depression is a confounding variable.

This will be explained to any participant who scores ≥ 15. For those with PHQ-9 scores ≤ 14

the OCI-R will be administered via the telephone.

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Participants who are eligible following initial screening will be invited to come to the

University to take part in the research. Participants will complete the STAI measures before

and after both the verbal and nonverbal components of the research. In the first instance

participants will complete both the trait and state components of the STAI. Participants will

complete verbal and nonverbal memory tasks, which will be counterbalanced. In the verbal

memory component participants will be presented with 20 words (neutral and OCD-relevant)

via speakers on a computer during encoding. Immediately following presentation,

participants will be asked to recall as many of the words as possible. The researcher will

record the order of the participants’ responses on paper that has the words listed. During the

30-minute delay participants will complete non-memory filler tasks that aim to distract

participants from the memory task. Following this, participants will be asked to recall as

many words as possible from the words they heard earlier. A recognition task will follow.

Participants will be asked to answer ‘yes’ or ‘no’ to whether they previously heard each of 40

words (20 Old/20 New words). They will be asked to rate their memory confidence on a

visual analogue scale (VAS) ranging from 0 (not confident at all) to 10 (very confident) for

each item. Participants will also be asked whether they have a conscious recollection of

hearing the word (remember), the word is familiar to them (know), or whether they are

completely unsure and guessing. Participants will complete another STAI following the

familiarity judgements.

The visual memory procedure is identical to the verbal memory procedure. However, as it is

nonverbal, during the encoding phase participants will be presented with 20 pictures on a

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computer screen. Participants will be asked to complete a STAI (state component only) just

before starting the nonverbal memory component, and also at the end.

Following data collection, participants will be given the opportunity to ask any questions they

may have and will be fully debriefed. Participants will be given information of local support

groups or referred back to their own support group as required. Control group participants

will be given details of the University’s centre of wellbeing. Refreshments will be provided at

the end of data collection.

The presentation of all stimuli will be on a computer (either by speakers or on the screen).

All responses will be recorded and scored by the researcher. For memory accuracy, one point

will be scored if an item is correctly recalled, and zero points will be scored if an item is

incorrectly recalled or not recalled at all. For organisational strategy, one point will be scored

for each word that is recalled consecutively from a specific category, or if the items are

recalled in the same order as presented. Memory confidence will be scored on a 0-10 VAS

and the total number of Remember Know Guess responses will be noted.

Ethical considerations

Name of Ethics Committee: University Ethics

Ethical principle Specific issue Overcoming the issueRisk Involves a vulnerable group Participants will be given

detailed information and will be given time to consider consenting. A full debrief will follow data collection.

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Could induce psychological distress and anxiety

Participants will be aware of this potential risk prior to giving consent (information sheet). A full debrief will follow data collection. Participants will be given general support as required.

Consent Gaining consent from participants All participants will give written consent on the basis of adequate information.

Withdrawal from the study Participants will be informed of their right to withdraw at any point during data collection, without any obligation to explain their decision or adverse consequences.

Storage of data All data will be confidentially stored. Participants will be informed that all data will be destroyed within 10 years.

Information regarding the study Participants will be given a detailed information sheet.

Confidentiality Identifiable information All data will be confidential. No identifiable information will be available if published.

Deception Withholding of information Participants will be informed that the study will involve memory tasks. They will not be informed that organisational memory strategy use is a dependent variable, as knowing this may compromise the results of the research and may not give a valid reflection of their everyday memory performance.

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Debriefing Withholding of information & Psychological distress and anxiety

Participants will be verbally informed of the study aims and hypotheses. They will be given information on the rationale behind using OCD-relevant stimuli. Details of local support groups will be given if required.

R&D Considerations

N/A

Proposed Data Analysis

Initially data will be screened for outliers (any data point that falls ≥3 standard deviations

from the participant group mean) and tests of normality will be performed (skewness in data

and Kurtosis).

2x2 mixed ANOVAs will be used to analyse the data for the main effects and interactions of

the independent variables on the dependent variables. ANCOVA will then be used to re-run

the analyses controlling for state anxiety.

Service User and Carer Consultation / Involvement

I met with Service User and Carer panel on 3rd July to discuss project and to gain feedback on

ethical issues and recruitment of participants. I also received feedback from the Service User

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Co-ordinator as well as my peers and a research tutor during a proposal presentation on 17th

July.

Feasibility Issues

Should the recruitment of an OCD sample from charities and support groups prove difficult, a

sub-clinical sample of University staff and students scoring above the OCI-R cut-off will be

used. OCD symptoms such as checking and washing are highly prevalent and research using

sub-clinical OCD samples and assessing memory has found evidence to support their

hypotheses (Sher, Mann and Frost, 1984).

The research requires a substantial number of participants and therefore researcher’s time.

However, the proposed research is part of a bigger project within the OCD research group at

the University of Surrey. Therefore, if recruitment proves difficult contingency plans will be

put in place for recruitment and data collection of the control participant group. Such plans

include partial data recording by an undergraduate student who would be supervised by Dr

Ellen Seiss, who also supervises this proposed research.

Designing OCD-relevant stimuli is a time consuming process and there will also have to

enough time to pilot the stimuli. Should this prove to be an issue the researcher would have to

use pre-existing word norm databases and picture databases without the OCD relevant

additional items. Although the researchers would like to pilot the stimuli extensively, piloting

will stop at the end of November. Pilot data until this point will be used to inform and guide

the stimuli selection for the main study.

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Dissemination strategy

Following the submission, the researcher plans to disseminate the findings to the “Journal of

Anxiety Disorders” and to present the findings to the charities/support groups that the OCD

participants were recruited from. There is a possibility that the findings may be presented at

annual OCD conferences, such as the OCD UK annual conference.

Study Timeline

MRP course approval – 06/08/2012 – 17/09/2012

Ethics submission – 30/08/2012-30/10/2012

Pilot – 17/10/2012 – 30/11/2012

Data collection – 01/12/2012 – 01/11/2013

Data analysis – 13/08/2013 – 01/01/2014

Draft introduction – 20/01/2013 – 20/08/2013

Draft method – 20/08/2013 – 02/10/2013

Draft results – 02/10/2013 – 10/01/2014

Draft discussion – 10/01/2014

Full draft due – 06/02/2014

Final submission – March 2014

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Deckersbach, T., Savage, C. R., Reilly-Harrington, N., Clark, L., Sachs, G., & Rauch, S. L. (2004). Episodic memory impairment in bipolar disorder and obsessive-compulsive disorder: The role of memory strategies. Bipolar Disorders, 6(3), 233-244.

Deckersbach, T., Savage, C. R., Dougherty, D. D., Bohne, A., Loh, R., Nierenberg, A., Sachs, G., & Rauch, S. L. (2005) Spontaneous and directed application of verbal learning strategies in bipolar disorder and obsessive-compulsive disorder. Bipolar Disorders, 7, 166-175.

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Hajcak, G., Huppert, J. D., Simons, R. F., & Foa, E. B. (2004). Psychometric properties of

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Olley, A., Malhi, G., & Sachdev, P. (2007). Memory and executive functioning in obsessive–compulsive disorder: A selective review. Journal of Affective Disorders, 104(1-3), 15-23.

Penades, R., Catalan, R., Andres, S., Salamero, M., & Gasto, C. (2005). Executive function and nonverbal memory in obsessive compulsive disorder. Psychiatry Research, 133, 81-90.

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Savage, C. R., Baer, L., Keuthen, N. J., Brown, H. D., Rauch, S. L., & Jenike, M. A. (1998). Organisational strategies mediate nonverbal memory impairment in obsessive-compulsive disorder. Biological Psychiatry, 45(7), 905-916.

Savage, C. R., Deckersbach, T., Wilhelm, S., Rauch, S. L., Baer, L., Reid, T., et al. (2000). Strategic processing and episodic memory impairment in obsessive compulsive disorder. Neuropsychology, 14(1), 141-151.

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Sher, K., Frost, R., & Otto, R. (1983). Cognitive deficits in compulsive checkers: an exploratory study. Behaviour, Research, and Therapy, 21, 357-363.

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Sher, K. J., Mann, B., & Frost, R. O. (1984). Cognitive dysfunction in compulsive checkers: further explorations. Behaviour Research and Therapy, 22, 493–502.

Shin, M. S., Park, S. J., Kim, M. S., Lee, Y. H., Ha, T. H., & Kwon, J. S. (2004). Deficits of organisational strategy and visual memory in obsessive-compulsive disorder. Neuropsychology, 18(4), 665-672.

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for the State-Trait Anxiety Inventory. Palo Alto, CA: Consulting Psychologists Press.

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MRP Systematic Literature Review

Are memory difficulties in OCD primarily due to organisational deficits during

encoding of information?

Proposed journal: Journal of Anxiety Disorders

7947 Words

Year 1

April 2012

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Abstract

BACKGROUND: Recent research in obsessive-compulsive disorder and memory

performance has focused on the possibility of memory deficits as secondary to executive

dysfunction, more specifically the failure to spontaneously implement organisational

strategies. AIMS: The current review aimed to identify and critique the literature that

administered organisational memory tasks to OCD and nonclinical control samples, and

focused on whether deficits in organisational strategy use mediated impaired memory

performance. METHODS: Systematic electronic searches of various databases (EBSCOHost,

Medline, PubMed, Science Direct) produced a final set of 15 papers for review. RESULTS:

Overall results are mixed. There is quite strong evidence for a mediating role of reduced

organisational strategy use on nonverbal memory performance, and less for verbal memory

performance. Although research in the verbal domain is limited. Key limitations of verbal

and nonverbal studies were the lack of an anxious control group, low ecological task validity,

different demands of memory tasks (implicit Vs. explicit) and small sample sizes.

CONCLUSIONS: The review identified a number of gaps in the current literature that may

provide explanations for the inconsistencies in results and made suggestions for future

research that may help to challenge these inconsistencies. Future questions could be - Is

reduced organisational strategy use OCD-specific or is it a general function of anxiety? Can

the inconsistencies in research be explained by a lack of ecologically valid tasks? Would

organisational strategy use remain poor if the tasks were idiographically designed? Would the

use of idiographic stimuli produce more consistent findings?

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Introduction

Obsessive Compulsive Disorder (OCD) is characterised by recurrent obsessions11 and/or

compulsions12 that cause marked distress and interfere with daily functioning. The

obsessions and/or compulsions must not be the result of a substance or general medical

condition, or restricted to a co-morbid Axis 1 diagnosis (Diagnostic Manual of Mental

Disorders 4th edition, American Psychiatric Association, 1994). The most commonly reported

obsessions involve the fear of contamination or doubts about past actions, which often leads

to compulsive behaviours such as repetitive washing and checking. For example, people with

obsessions involving doubt over past actions commonly engage in checking behaviours, such

as checking they have locked the door or turned off the stove. It has been suggested that OCD

should be viewed as a heterogeneous disorder as the underlying mechanisms of the different

obsessions and compulsions are argued to be different (Lochnor and Stein, 2003) and as such

OCD patients are often classified according to their obsessions and compulsions, such as

checkers, washers and obsessionals (where the person does not have observable compulsions

and so usually take the form of excessive rumination to neutralise their obsessions). Viewing

OCD as heterogeneous has important clinical and research implications; however there is

often considerable overlap of symptomology making it difficult to clearly distinguish

between ‘sub-types’ (Segalas et al, 2008).

11 Obsessions: intrusive thoughts, impulses or images that cause significant distress to the individual.

12 Compulsions: repetitive behaviours or mental acts aimed at neutralising the obsession with the aim of reducing the level of distress

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Many theories from differing schools of thought have been proposed regarding the

development and maintenance OCD. Early theories placed importance on religion and

asserted that intrusive thoughts were the work of Satan. Alternatively, learning theories argue

that obsessions and compulsions are abnormal learned responses to a fear they have

developed via association (de Silva and Rachman, 1992). Therefore compulsive behaviours

that aim to reduce distress serve to maintain it as they reinforce the fear. Cognitive theories

emphasise the importance of the misinterpretation of intrusive thoughts, which cause the

distress and lead to neutralising behaviours, such as avoidance and compulsions (Salkovskis,

1985). More recently, neuropsychological theories of OCD and neuropsychological research

have been based upon clinical observations and emphasis tends to be placed upon attention,

executive functioning and memory.

Given the chronic doubting reported in OCD, it appears somewhat intuitive to implicate the

role of memory processes. Initial research into memory functioning in OCD suggested a

global memory deficit hypothesis (Sher, Frost and Otto, 1983) – that is memory dysfunction

was seen as present in OCD regardless of the modality of material presented. The global

memory deficit hypothesis was also particularly implicated for OCD patients with checking

symptoms, as this appears to be a more logical association. For example, the urge to

repeatedly check that one has turned off the stove may be related to a memory deficit, in that

they may have forgotten they had previously checked. As a result, the memory domain has

received much research attention in the last 20 years; however it has produced inconsistent

findings. Although the literature appears to point to nonverbal memory deficits, verbal

memory has been reported to be comparable to that of nonclinical control participants. This

conflicting evidence concerning memory functioning in OCD suggests that a global memory

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deficit may not be a plausible explanation of the neuropsychological profile in OCD (Jelinek

et al, 2006). Reviews into memory functioning in OCD have concluded that the memory

deficit hypothesis is not well supported by literature and suggested that memory difficulties

may be related to other neuropsychological functions, such as executive dysfunction (Harkin,

Rutherford & Kessler, 2011; Kuelz, Hohagen & Voderholzer, 2004).

Research into executive dysfunction in OCD has highlighted that although OCD participants

often perform comparably to nonclinical controls in terms of overall achievement, there often

are increased reaction times, perseveration on previous items, and increased difficulty to

change set when given feedback (Olley, Malhi and Sachdev, 2007). There are a number of

hypotheses relating to why such patterns exist, such as the deficits being secondary to

attempts to avoid mistakes, reduced ability to spontaneously generate new strategies and a

failure to implement organisational strategies.

Recently, the role of organisation has been researched as a potential primary deficit in OCD,

especially in relation to memory deficits. This work stemmed from neuroimaging research

that provided consistent evidence of dysfunction in the frontal-striatal pathway in OCD

(Rauch and Baxter, 1998); a key brain region thought to be responsible for strategic processes

of memory. Therefore, it may be that OCD patients have difficulties with strategic

processing in memory, for example, they have difficulty with identifying and using semantic

and perceptual features of stimuli to aid their memory recall, which is an area that closely

relates to executive functions, specifically organisation. Tasks tapping into the strategic

aspects of memory involve participants recalling verbal or nonverbal material, which has

embedded structure, meaning that there the material has a coherent form and the features can

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be used in such a way to better encode and organise the information; this usually leads to

faster response times and better retention of information. This hypothesis has been researched

more so in relation to nonverbal memory than with verbal memory and produced promising

results that may suggest such a deficit impedes encoding on nonverbal information. It may,

therefore be a key neuropsychological factor in OCD. The purpose of the current review is to

identify and review the empirical literature that has looked at organisational strategies in

memory tasks as a possible primary marker of OCD. The review aims to identify both

consistencies and inconsistencies in the literature and to develop hypotheses as to why these

similarities and differences arise within the OCD population. It is hoped that a clearer picture

will result from the review and possible future directions for research will be discussed.

Methods

Search Strategy

Research papers were collected through systematically searching EBSCOhost, SciVerse, ISI

Web of Knowledge, MEDLINE, PubMed and Science Direct. All papers published up to

January 2012 were included in the search and reference lists from relevant articles were also

searched. Content of papers were searched using the following terms: OCD or obsess*

compuls* AND memory OR/AND recall OR recog* OR free OR verbal OR visual AND

strat* OR assoc* OR organis* OR executive function.

Searching the different databases produced an average of 150 articles. Initially the titles were

scanned for relevance. The abstracts of the identified articles were then scanned before a 158


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decision was made as to whether they were relevant to the review. Reference lists of the

articles were also hand searched. This led to a final set of 15 papers to be included in the

literature review.

Inclusion criteria

The inclusion criteria for the searches were (1) peer reviewed journal articles with the year of

publication 1995-present, (2) papers written in the English language, (3) working age adults

(18-65 years with a diagnosis of OCD as confirmed by the DSM-IV (APA, 1994) or to be

classed as sub-clinical OCD as confirmed by a validated measure of OCD, (4) papers that

investigated the effect of OCD and anxiety on memory performance (explicit and implicit

memory), (5) memory tasks that assessed organisational strategy use.

Results

A lot of research has been completed within OCD assessing memory and executive

functioning; however the purpose of the current review is to solely focus on research that has

used organisational memory tasks, that is, tasks assessing both memory accuracy and

organisational strategy use. Following the inclusion criteria, the systematic search produced

15 papers, which will be the focus of the review. All studies were conducted in outpatient

settings, with the majority of the studies being conducted in Europe (n=5), and the United

States of America (n=5). The articles have been grouped into the following categories: (I)

nonverbal memory and organisation tasks, (II) verbal memory and organisation tasks, (III)

verbal and nonverbal memory and organisation tasks. Tables 1 and 2 (Appendix 1) outline

the key findings of the studies, which are organised by studies addressing nonverbal memory 159


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and organisational skills (Table 1) and verbal memory and organisational skills (Table 2).

Studies that assessed nonverbal memory as well as verbal memory and organisational skills

are presented in Table 1, with the verbal aspects in blue.

Nonverbal memory and organisation tasks

The question of whether memory deficits in OCD are mediated by organisational strategy use

has been researched using nonverbal memory tasks (See Appendix 1, table 1 for a summary

of results), and has predominantly been assessed using the Rey Osterrieth Complex Figure

test (RCFT; Rey, 1941).

The RCFT is a complex line drawing that participants are initially asked to copy. The

standardised procedure of the task, as reported in Lezak (1995) states that during the copy

condition, the participants should be given coloured pencils, which should be changed when a

section of the figure has been copied, and the examiner should closely observe noting the

order of colours. This gives the examiner an idea of the procedural method the participant

used and helps determine whether the participant used a configurational (that is copying and

recalling the figure by identifying the main organisational features of the figure, of which

there are five) or a part-oriented (that is initially copying and recalling the smaller detailed

components of the figure that are not one of the five main organisational components)

approach to the task. The examiner may choose to reproduce the participant’s copy and

number each unit in the order they were copied, rather than use coloured pencils. Although

there is no time limit for the copy condition, time taken to complete the copy is recorded.

During the copy condition participants are not informed that they will be asked to reproduce

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the figure from memory making it an implicit memory test. Recall intervals are normally

immediate and delayed (20-30 minutes) and is followed by an ‘old/new’ recognition test

consisting of 24 items.

The RCFT can be scored both quantitatively and qualitatively. The quantitative scoring

system (Osterrieth, 1944) is based on the presence and accuracy of the 18 elements of the

figure, with each element having two points available. There are two qualitative scoring

systems that have been used in the current literature review. The Boston Qualitative Scoring

System (BQSS; Stern et al, 1994) and the Savage et al (1999) method look at the process of

figure production in order to gain information about a person’s organisational and perceptual

abilities. The BQSS is most commonly used and provides a numerical score based on the

main configural elements, clusters, and detail, therefore providing a comprehensive

assessment of performance in relation to presence, accuracy, and organisational strategy.

Savage, Baer, Keuthen, Brown, Rauch, and Jenike (1998) were the first researchers to assess

organisational strategy use in OCD, and were particularly interested in whether reduced use

of organisational strategies mediated nonverbal memory performance. Administering the

RCFT and various tests of executive functioning to unmedicated OCD participants and

nonclinical controls, Savage et al found that the OCD group performed significantly poorer

than the nonclinical controls both quantitatively and qualitatively on the RCFT; however they

showed good retention of the information across the time delay suggesting a deficit during

encoding of the figure rather than storage or retrieval of the figure. Using a mediation model,

the authors reported significant correlations between the RCFT copy organisation scores and

the recall scores; therefore implicating that organisational deficits at encoding mediate

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nonverbal memory recall. Further analyses indicated that the organisational deficits may be

related to set shifting13 difficulties. Although this study controlled for medication, no

information was available relating to comorbidity of other Axis 1 diagnoses, which may have

influenced the data. The sample size was small and so may not have had enough statistical

power to produce a reliable finding in OCD that can be generalised as a specific feature of

OCD. Additionally, no information was given relating to OCD subtype scores; this is

problematic as previous literature points to memory deficits being more pronounced in

obsessive compulsive checkers (Woods, Vevea, Chambless and Bayen 2002). However,

recent research has noted that checkers may not be impaired in memory per se, but instead

impaired in meta-memory (Cuttler and Graf, 2009), that is they have reduced knowledge of

and confidence into their memory abilities.

Penades, Catalan, Andres, Salamero and Gasto (2005) compared OCD patients and

nonclinical controls (n=35 and 33 respectively) performance on a range of tasks including

tests of executive functioning, the RCFT and the Faces subtest of the Wechsler Memory

Scale 3rd edition (WMS-III; Wechsler, 1945) – a task that requires minimal organisational

strategies, and therefore giving a different measure of visual memory. Quantitative and

qualitative scoring of the RCFT using Savage et al’s method highlighted that the OCD group

performed significantly worse than the nonclinical controls in relation to immediate recall of

the RCFT and on the organisation measure of this task. However, no differences were found

between the participant groups for the faces subtest of the WMS-III, suggesting the nonverbal

memory deficit appears only to be present when skills in implementing organisational

strategies are required. It might also be linked to task difficulty, in that the RCFT task is more

13 Set shifting: the ability to be alternate between tasks and mental sets in direct response to changing environmental cues

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difficult than the Faces task. Penades et al also found that the significant differences in

immediate memory were indirectly associated with poor use of organisational strategies at

encoding, thus supporting a mediating role for organisational strategies during encoding.

However, small samples that were not matched for age and sex were used, which may be a

confounding factor as Segalas et al (2010) reported that there may be sexual dimorphism in

OCD memory deficits; in their study males performed significantly worse than the male

nonclinical control participants whereas females performed comparably to their matched

nonclinical controls. In addition there was no anxious control group and so it is difficult to

ascertain whether the impairments detected are OCD specific or due to state anxiety; indeed

this is a limitation of most research into organisational deficits and memory in OCD. In

relation to medication, although some of the participants were using prescribed medication,

analysis found that there was not a significant difference between the medicated and

unmedicated OCD participants. They also used the Beck Depression Inventory (BDI) to

measure depressive symptoms; they found that scores remained significant on all

neuropsychological measures when depressive symptoms were controlled for, which may

point to a deficit that can be accounted for by OCD, but not co-morbid depression.

Shin, Park, Kim and Lee (2004) and Jang et al (2010) used the RCFT in isolation of other

neuropsychological tasks to assess nonverbal memory and organisational strategy use. Both

studies found that the OCD groups were significantly impaired at both immediate and

delayed recall and had poor planning and organisation abilities. However, Jang et al used

factor analysis on the YBOCS scores of the OCD group (n=144) and found that nonverbal

memory impairment was related to the symmetry/ordering dimension, whereas the reduced

use of organisational strategies to the obsessions/checking dimension. Key limitations of Jang

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et al’s study include the OCD group including (but not controlling for) patients who had co-

morbid major depressive disorder if their primary diagnosis was OCD; an important factor to

consider, given that several pieces of literature highlight the role of depression in memory

impairment (Burt, Zembar and Niederehe, 1995), and co-morbid depression seems to highly

influence neuropsychological test performance (Moritz et al, 2001). Shin, Park, Kim and Lee

had a smaller sample (OCD n=30, nonclinical controls n=30) and failed to replicate previous

findings (Savage et al, 1999; Penades et al, 2005) that supported a mediating role of reduced

organisational strategy implementation on nonverbal memory performance.

Although the RCFT is commonly used to assess nonverbal memory and organisational

abilities, it has some limitations. The key limitation is that original standardised instructions

are not always adhered to, mainly due to its popularity. An important difference in research

literature concerns the timing of recall trials, for example, the delayed recall condition is

completed between 15 and 60 minutes. A further limitation is that due to its complexity and

requirements many researchers vary in their use of and scoring of the figure and so it is

important to be aware of this when interpreting data, as such differences in administration

and scoring may make it difficult to directly compare findings and make firm conclusions

based on the data.

Summary of RCFT findings

Research into the mediating role of organisational deficits on nonverbal memory using the

RCFT has produced fairly consistent findings supporting a mediating role (Savage et al,

1998; Penades et al, 2005); however, a study using a large sample found that organisational

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deficits did not mediate nonverbal memory deficits in OCD (Shin et al, 2004). Inconsistent

findings may be due to a number of methodological weaknesses of the studies, such as the

use of small samples which make it difficult to reliably disregard the null hypothesis and

therefore to make firm conclusions about a mediating role of organisational deficits and

nonverbal memory. Further, the research aforementioned failed to include an anxious control

group and so it is difficult to rule out the possibility that the results found in support of a

mediating role may be due to state anxiety, rather than being an OCD-specific deficit.

A further task used to assess nonverbal working memory and organisational strategy is the

Spatial Working Memory task (SWM) from the Cambridge Neuropsychological Test

Automated Battery (CANTAB). This task looks at participants’ ability to retain and

manipulate visual items in working memory. Participants are presented with a several boxes

on a computer screen (the number of boxes increases as the test progresses) and are required

to select boxes one at a time to find a blue token. Participant’s have to develop a strategy to

identify the sequence of where the blue token is located, as a blue token will only be in one

box at a time, whilst making a minimal number of errors. Outcomes of the task include

number of errors, response time and strategy use.

Simpson, Rosen, Huppert, Lin, Foa and Liebowitz (2006) used the SWM task, the RCFT and

other measures of visual memory to assess the reliability of neuropsychological deficits in

OCD. Their matched samples, although small in each group, included current OCD (n=30),

comorbid OCD (n=15), history of OCD (n=15) and nonclinical controls (n=35). Results

indicated no significant differences between the four sample groups on the measures;

however when the current OCD group was compared to the nonclinical controls a significant

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difference was found on the Benton Visual Recognition Test (BVRT; Benton, 1992), which

measures immediate nonverbal memory for abstract line drawings. It is therefore questioned

whether there are reliable neuropsychological deficits in OCD as the impairment was only

found on one test of visual memory and not others, making it difficult to conclude global

visual memory impairment. However, it is important to note that the demands of the BVRT

and the RCFT differ as the BVRT is an explicit memory test, therefore the participants are

aware of the recall trial, whereas the RCFT is an implicit memory test and the participants are

not aware of the recall trials. This is important as during the BVRT participants are more

likely to implement memory strategies to aid their performance, whereas during the RCFT

they are unlikely to do this unless they are already aware of the task from previous

knowledge or participated in similar research. Importantly there were no differences between

the groups in organisational strategy use when completing the RCFT, which is in contrast to

other literature (Savage et al, 1999). To critique the study, Simpson et al noted that they did

not determine treatment history of the OCD sample and so therefore not exclude the

possibility that type, length of, or time since treatment may have influenced the findings. The

significant difference found in the study also may not be specific to OCD, as impaired

performance on the BVRT in comparison to nonclinical controls has also been reported in

other anxiety disorders (Cohen et al, 1996). They also did not control for use of medication in

the OCD sample, and despite evidence suggesting that the use of medication in OCD is not

influential in neuropsychological tests (Purcell, Maruff, Kyrios, and Pantelis 1998), it is

difficult to rule this out conclusively.

In a similar study, Nedeljkovic et al (2009) compared performance on the SWM task from the

CANTAB, in medicated clinical samples of OCD checkers, washers, obsessionals, mixed

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symptom profile as well as nonclinical control participants. They reported significant

differences between the OCD groups and nonclinical controls on the SWM task, noting that

checkers had significantly reduced ability to develop and implement organisational strategies

to enhance their performance. Additionally, OCD checkers and the mixed symptom group

made more errors on visual recognition tasks and took longer to initiate responses on the

spatial planning task in comparison to the nonclinical controls. Visual recognition memory of

the checkers was impaired in comparison to the OCD washers group, and the obsessionals

made more spatial recognition errors. The findings therefore offered some support to the

hypothesis that OCD subtypes have different neuropsychological profiles in relation to visual

memory abilities.

Summary - nonverbal memory and organisation tasks

In summary, research into a mediating role for organisational deficits on nonverbal memory

impairments in OCD has been fairly consistent using a number of different tasks. However, it

may be difficult to draw firm conclusions from on these studies as the majority have recruited

small samples and have not included an anxious control group, making it difficult to ignore

whether memory deficits are a result of state anxiety. The majority of research discussed also

did not include information regarding OCD subtypes, which appears to be important, as the

research that did address this found that OCD checkers were more likely to make visual

recognition errors (Nedeljkovic et al, 2009) and present with organisational deficits that

mediate their visual memory impairments (Jang et al, 2010). Indeed, it seems more intuitive

that people who doubt their past actions would be more likely to present with memory

impairment, with previous research finding that people who report excessive checking doubt

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their ability to accurately whether they have completed a task as they intended to (Rachman

and Shafran, 1998) and so is in support of these studies that have found different

neuropsychological profiles for different OCD subtypes.

Verbal memory and organisation tasks

Few studies have looked solely at verbal memory and the role of organisational strategy use,

due to the majority of research into verbal memory in OCD reporting comparable

performance to nonclinical controls (Kuelz, 2004). Nonetheless a small number of studies

have addressed this area given the apparent role of organisation in nonverbal memory (see

Appendix 1, Table 2 for a summary of results). Verbal memory tasks that allow for the

assessment of organisational strategy use are ones that include categorisation of word lists,

for example the California Verbal Learning task (CVLT; Delis, Kramer, Kaplan, & Ober,

1987). The CVLT consists of a list of 16 words, which are read aloud to participants over five

learning trials. The words are semantically related and can be grouped in to one of four

categories. Participants are not informed that the items can be categorised, and the words are

presented so that no two words from the same category are presented consecutively. An

interference list of 16 words is read aloud following the fifth learning trial. Free recall is

measured following each trial, and overall scores are recorded for short and long term recall,

organisation of recall, and auditory recognition.

Deckersbach, Savage, Reilly-Harrington, Clark, Sachs and Rauch (2004) addressed the role

of organisational strategy use with the CVLT in three samples: OCD (n=30), Bipolar I

(n=30), and nonclinical controls (n=30). The study used these clinical samples as the

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prefrontal cortex, an area thought to be important for the use of organisational strategy, is

implicated in both OCD and Bipolar I. The participant groups were matched for age, sex and

education; in addition the clinical samples were matched for age of onset and length of

diagnosis. Only the results of the OCD sample will be noted. In comparison to nonclinical

controls, the OCD group was significantly impaired on measures of delayed recall and used

significantly fewer organisational strategies, meaning they were less likely to cluster words

according to their semantic category. Further analysis indicated that the delayed recall

performance was mediated by the reduced use of organisational strategies during encoding.

The authors controlled for a range of variables such as medication, depressive symptoms and

comorbid diagnoses, and found that these variables did not significantly influence the results

and so can be ruled out as potential mediating factors.

A follow up study with smaller samples of OCD (n=20), BP-I (n=20) and nonclinical controls

(n=20), Deckersbach et al (2005) used an auditory verbal encoding paradigm, which

consisted of three conditions (spontaneous, directed, unrelated). Participants listened to two

lists of either categorised or uncategorised pre-recorded words through computer speakers. In

the spontaneous condition 24 words were presented from four categories, with no two words

from the same category presented consecutively. Participants were not informed that the

words could be categorised. In the directed condition, the word list was different (as were the

categories) and the participants were instructed to group the words into their categories. In

the unrelated condition 24 words from 24 different categories were presented and participants

had to encode the words in any order, after being told that the words could not be categorised.

Each encoding condition was presented twice. Following each encoding condition

participants were asked to immediately recall the words; after the second presentation of the

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spontaneous and directed conditions participants were asked to recall words from specific

categories. The experiment ended with an ‘old/new’ recognition test. Results highlighted that

the OCD group was less likely than the nonclinical control group to spontaneously implement

organisational strategies, but this did not impede their recall performance in the spontaneous

condition. Furthermore, in the directed condition the OCD group was able to use

organisational strategy, and performed comparably in the recognition condition. The authors

noted that the performance of the clinical samples might have been influenced by their

involvement in previous research, as some of the participants had been part of similar

research using the same paradigm. One limitation of the Deckersbach et al (2004, 2005)

studies is that no non-OCD anxious control group was included; indeed this is a limitation of

most research into organisational deficits and memory in OCD. This may have led to

interesting findings relating to whether this semantic clustering deficit is specific to OCD, or

whether it is found in other anxiety disorders. However, it is possible that they did not do this,

as their interest was to compare findings to BP-I and therefore the focus of the research was

not anxiety.

Sawamura, Nakashima, Inoue and Kurita (2005) were interested in whether people with OCD

would benefit from being shown the semantic structure of the task. They used Iddon,

McKenna, Sahakian and Robbins (1998) verbal strategy task to do this with a small sample of

OCD patients (n=16) and matched nonclinical controls (n=16). The task had three stages; in

the first stage participants were shown a list of 20 words (from five categories) for one

minute. As with the CVLT, words from the same category were not presented consecutively

and so appeared unrelated. Participants were asked to recall the items and to complete an

‘old/new’ recognition task. The next phase was a training phase, whereby participants were

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shown the same words and the five semantic categories. They were required to categorise the

words as quickly as possible, with the knowledge that there were an equal number of words

per category. The final stage of the task was identical to the first stage but consisted of new

words and new categories. Results indicated the OCD group were significantly slower to

semantically cluster the words, had significantly poorer recall and recognition, and used

significantly less organisational strategies in the recall tasks. The slower reaction times in

semantically clustering the items were found to contribute to the impaired free recall

performance. One key weakness of the study was that the verbal strategy task has not been

validated for clinical use despite it being commonly used in research studies with different

populations. Also, the study used late-onset patients and so it may be unclear if their

cognitive difficulties are OCD-specific or related to organic causes (Swoboda and Jenike,

1995).

Summary – verbal memory and organisation tasks

There is not much research looking solely at verbal memory and organisational deficits, as

early research into verbal memory in OCD pointed to it being relatively well preserved

(Olley, Malhi and Sachdev, 2007). Nevertheless, research that has been conducted into this

area has produced largely supportive results for deficits in organisational strategy use and

verbal memory impairment in OCD. However, only one study has found support for a

mediating role (Deckersbach et al, 2004), whereas the others have found impaired

spontaneous use of organisational strategies but did not address the possibility of a mediating

role (Sawamura et al, 2005). A key limitation of the studies is that no anxious control group

was included and so it may be that the deficits are a result of heightened anxiety. Further, the

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word list tasks used are not specific to OCD and so it is possible the findings are not

representative of what is happening neuropsychologically in OCD. Future studies should take

into account the possibility of late onset, and also complete further analysis into the

possibility of a mediating role of organisational deficits on verbal memory impairments,

using more representative and ecologically valid stimuli that is specific to each individual’s

OCD obsessions and compulsions.

Verbal, nonverbal memory and organisation tasks

Various studies addressing nonverbal memory deficits have also included measures of verbal

memory in order to gain insight into the role of organisation in both domains and to compare

this performance in the same samples (see Appendix 1, Table 1 for summaries of results;

verbal memory results are in blue).

Savage, Deckersbach, Wilhelm, Rauch, Baer, Reid and Jenike (2000) assessed both verbal

and nonverbal memory and use of organisational strategies in OCD and nonclinical control

sample groups using the CVLT and RCFT (organisational strategy use was assessed using

Savage et al’s, 1999 procedure). Relative to nonclinical controls, the OCD group were

significantly impaired on free recall of both verbal and nonverbal material. Using a mediation

model, Savage et al found that reduced spontaneous use of organisational strategy in the

OCD group mediated poor recall of verbal and nonverbal material. They concluded that OCD

patients are primarily impaired in strategic processing abilities rather than memory abilities,

as impairments seem to be present only when memory tasks require organisational skills, but

noted that it is important not to infer neuroanatomical abnormalities from the findings, as the

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neuropsychological tasks used are an indirect measure of brain function. Although verbal and

nonverbal memory were assessed in relation to organisation, other tests of executive

functioning were not used, which may make the study less comprehensive than others in the

field. The sample size of the two groups were also small and so perhaps studies with larger

samples would be useful and may be able to better assess potential different

neuropsychological profiles for different subtypes. Although, it has been argued that looking

at OCD symptomology as distinct categories may not be a true reflection of those with the

diagnosis as it is estimated between 42-77% of people with OCD have comorbid mental

health difficulties (Segalas et al, 2008); therefore to exclude comorbid psychiatric diagnoses

may result in very small sample sizes that would not be able to yield enough statistical power

to disregard the null hypothesis in experimental studies.

Segalas et al (2008) completed a similar study to that of Savage et al (2000), using the RCFT

and the Spanish equivalent to the CVLT, The Spain-Complutense Verbal Learning test

(TAVEC; Benedet and Alejandre, 1998). It shows similar psychometric properties and the

characteristics of the test are highly similar to the CVLT, making it possible to compare

results gained from the two tests (Benedet and Alejandre, 1998). Comparing the results of 50

OCD participants to that of 50 matched nonclinical controls, Segalas et al found that the OCD

participants were significantly impaired on immediate and delayed recall of verbal and

nonverbal information. An interesting finding from this research was that an older age of

onset was related to poorer performance on the verbal memory task. It has been hypothesised

this may relate to brain maturation (Friedlander and Desrocher, 2006), but may partly be due

to the cut-off point used to differentiate between early and late onset. Limitations of the

Segalas study are that the RCFT and TAVEC may not be directly comparable organisational

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memory measures as the demands of the two tasks differ. In the TAVEC, as with the CVLT,

participants are aware that they will be asked to recall the words again, whereas when

completing the RCFT participants are not aware of the memory component, and so

participants may initiate the use of memory strategies in the CVLT to aid their overall

performance, whereas for the RCFT they are unlikely to do this unless they are familiar with

the task or the aims of the research. They also did not assess executive functioning further,

which appear to play an important role and may have provided additional pertinent

information regarding the neuropsychological profile of people with OCD.

Interestingly a follow-up study suggested that there might be sexual dimorphism in OCD

(Segalas et al, 2010). They found that males with OCD were more likely to perform poorly

on the RCFT in comparison to matched nonclinical controls, whereas women performed

comparably to controls on the TAVEC and the RCFT. Difficulties with the follow-up study

were that OCD symptoms were not assessed for in the control groups and so the possibility of

subclinical participants being in the control groups cannot be ruled out, and may have

influenced the results. However, this is an interesting finding and may be something worth

consideration if samples are large enough to accommodate this.

Exner, Kohl, Zaudig, Langs, Lincoln and Rief (2009) assessed verbal and nonverbal memory

performance in matched samples of OCD (n=23) and nonclinical control participants (n=22)

using the CVLT and the RCFT. The WMS-R Logical Memory subtest was used to assess

memory for complex verbal information. They found that although the OCD participants

were impaired on recall of complex verbal information, they performed comparable to the

controls on the list learning task (CVLT) and the complex visual task (RCFT). In contrast to

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Savage et al (2000), Exner et al found that although the OCD group used less organisational

strategy this did not compromise their free recall. It may be that the sample size was not large

enough to yield a significant difference between the OCD and nonclinical control groups;

however such inconsistencies in the literature highlight the need of further research to

understand the reasons for discrepancies.

A few studies were interested in the effects of comorbidity on memory performance in OCD

due to inconsistencies in the literature. Aycicegi, Dinn, Harris and Erkmen (2003) compared

small samples of OCD participants with matched nonclinical controls on the Repeatable

Battery for the Assessment of Neuropsychological Status (RBANS; Randolph, 1998) and

various tests of executive functioning. Measures of schizotypal personality and depression

were also administered. Results indicated that although the OCD sample was impaired on

delayed recall of verbal and nonverbal material, these differences remained when the effects

of depressive and schizotypal symptoms were controlled for in the analysis; therefore

suggesting an OCD-specific deficit, or at least a deficit that cannot be accounted for by

schizotypal or depressive symptoms.

Rampacher, Lennertz, Vogeley, Schulze-Rauschenbach, Kathmann, Falkai, and Wagner

(2010) were interested in visual processing and comorbidity. They compared matched OCD

patients, Major Depressive Disorder (MDD) and nonclinical controls on the RCFT, and the

German equivalent to the CVLT. The three groups performed comparably on all verbal

memory measures; therefore consistent with recent reviews suggesting that verbal memory is

relatively well preserved (Kuelz, Hohagen, and Voderholzer, 2004). The OCD group showed

significantly poorer perception and manipulation of complex visual information than the

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nonclinical controls, which was also significantly correlated with OCD symptom severity.

The OCD group performed significantly worse than the other samples on organisational

measures of visual memory, which may be a result of reduced perceptual abilities. As the

MDD group did not show the visual perception and visual memory impairments this deficit

may be OCD-specific, or at least present in OCD but cannot be accounted for by comorbid

MDD.

Summary – verbal, nonverbal memory and organisation tasks

In comparing both memory modalities in OCD samples, one is able to gain a direct

comparison within the same sample, meaning that a better representation of memory in OCD

may be gained. However, there appears to be some level of inconsistency in the literature,

which may be related to the nature of the tasks. One study found that the OCD sample was

not impaired on verbal list learning tasks, but were impaired for complex verbal information

in the form of prose (Aycicegi et al, 2003). This may be an important consideration for future

studies and as discussed previously using OCD relevant material may produce different

findings to those that have been reported in this review. Also, the demands of verbal and

nonverbal tasks in the studies are different, as the RCFT is an implicit memory task whereas

the word list tasks are explicit memory tasks; the problems with which have previously been

discussed. Again, future work may want to address this specifically by using both verbal and

nonverbal memory tasks that have more similar demands, as this may give a better

comparison of data and so a more valid reflection of memory performance in OCD.

Overall summary

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In summary, the literature reviewed has pointed to both verbal and nonverbal memory

deficits when organisational strategies are accounted for. However, results are sometimes

conflicting, which illustrates the need for further research into OCD and memory

impairments. Many of the studies share limitations such as failing to control for the use of

medication, comorbid Axis 1 disorders, and not using comparative control groups; for

example it may be useful to use an anxious control group to rule out the role of state anxiety.

Such limitations make it difficult to draw firm conclusions that the memory and

organisational strategy impairments are OCD specific. A further key limitation is the

ecological validity of the tasks used, as standardised measures may not be sensitive enough to

gain a true picture of memory functioning in OCD. Nonetheless, much research has been

fairly comprehensive in testing for both memory deficits and executive dysfunction, and it

may be questionable as to whether all avenues have been exhausted in the area of memory in

OCD.

Discussion

The presented literature highlights that although there is evidence to support the mediating

role of organisational strategies in memory deficits in OCD there may still be unanswered

questions due to the inconsistency in the literature. The majority of studies assessing

nonverbal memory using the RCFT find that OCD groups differ significantly from

nonclinical controls (for example, Savage et al, 1999, 2000), except for Exner et al (2009)

who reported comparable performance between the OCD and nonclinical controls. Although

most find that OCD groups are less likely to use organisational strategies (Segalas et al,

2008), not all of these studies support a mediating role for organisational strategy use in

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relation to nonverbal memory deficits (Shin et al, 2004). Findings in relation to verbal

memory and organisational strategy are reported, but less consistently. Whilst some studies

have found both reduced recall and a mediating role for organisational strategy use (Savage et

al, 2000; Deckersbach et al, 2004), others have reported no differences in performance (Exner

et al, 2009). Possible reasons that organisational and memory deficits are not consistently

reported are that the task and stimuli may not be sensitive enough to elicit differences

between OCD groups and nonclinical control groups, the demands of the tasks differ (explicit

Vs. implicit memory tasks), lack of an anxious control group, small sample sizes, the role of

medication and comorbid psychiatric diagnoses, age and length of onset and the clustering of

subtypes. A number of these possible explanations will be discussed further.

With such inconsistencies in the literature there may be other explanations that have not yet

been explored. One argument to support a mediating role of organisational strategy in

memory performance in OCD comes from cognitive training literature. Buhlmann et al

(2006) investigated whether organisation impairments could be alleviated by cognitive

training in people with OCD and nonclinical controls. Prior to being randomly assigned to the

training condition all participants completed the copy trial of the RCFT. The training

condition in the study was designed to improve the ability to process complex visual

information in a meaningful way, and the Taylor Complex Figure was used to facilitate this.

A second copy, and recall of the RCFT followed the training condition. Although the training

procedure helped to improve organisation and recall relative to baseline measures in both

samples, OCD participants improved in their organisational strategy use during encoding

whether they had received the training or not. This suggests that people with OCD may have

difficulty spontaneously implementing organisational strategies for complex nonverbal

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information. A key limitation of this study is the lack of ecological validity, which makes it

difficult to determine whether the organisational skills training will help to reduce their level

of distress in their everyday life. Park, Shin, Ha, Shin, Kim, Lee, and Kwon (2006) designed

a cognitive training programme consisting of nine 60-minute sessions to be delivered to an

OCD sample. Performance on both the RCFT and the Korean-CVLT were assessed before

and after training in comparison to nonclinical controls (the nonclinical control group did not

receive any form of training). Memory function and organisational scores in the OCD sample

had significantly improved in the nonverbal task, consistent with previous studies finding a

mediating role for organisational strategies on memory performance (Savage et al, 1999).

However, their performance on the verbal task reduced, suggesting that cognitive training on

organisational skills may not be relevant to verbal memory in OCD, and is consistent with

previous findings disputing a mediating role for organisational deficits in verbal memory

(Exner et al, 2009).

One important question to come out of the review is whether the impairment reported are

OCD-specific or are a function of anxiety; that is are we all susceptible to memory

impairments and organisational deficits when we are anxious. A review by Coles and

Heimberg (2002) addressed memory and anxiety disorders; they found that the literature is

largely inconsistent or in its early stages. They found that in relation to OCD there is an

explicit memory bias for OCD-relevant material; that is people with OCD appear to find it

difficult to more forget OCD relevant material than nonclinical controls, but further evidence

is needed to support this conclusion. The function of a memory bias in relation to threat

information and anxiety certainly makes sense form an evolutionary perspective as when in a

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threatening environment people are more likely to be hypervigilant to the environment and

retain the threatening information.

Given this information, it is surprising that few studies have looked at idiographic stimuli14 to

address the inconsistencies in the OCD memory literature. Given the heterogeneity in OCD

this may be an important consideration for future researchers, as using individual or subtype

specific stimuli may produce findings that offer a possible explanation for the inconsistencies

in the OCD memory literature. Tolin, Hamlin and Foa (2002) used idiographic stimuli and

verbal memory performance in an OCD sample to both anxious controls and non-anxious

controls using a directed forgetting paradigm. This involves clear instructions being given to

the participants during the encoding phase of the experiment to remember or forget certain

words immediately following their presentation; but during recall they are asked to recall all

words that were presented to them regardless of the original instruction. They found that

although there were not any significant differences between groups for free recall; the OCD

group had greater impaired forgetting in the recognition task. There were no differences

between the anxious controls and non-anxious controls, which indicates that impaired

forgetting of OCD-relevant material may be OCD-specific, and therefore not a function of

anxiety per se. Further studies support the finding of enhanced memory for personally salient

information in people with OCD, for example Wilhelm, McNally, Baer, and Florin, 1996;

Radomsky and Rachman (1999) also used words in a directed forgetting paradigm, and a

ecologically valid task relating to contamination fears; however, there appears to be a lack of

literature into verbal memory and organisation that uses OCD relevant material in the form of

prose, or indeed words that also assesses organisational strategy use. Harkin, Rutherford and

14 Idiographic stimuli: specific to the each individual’s obsessions and/or compulsions180


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Kessler (2011) reported that a group of subclinical checkers showed greater memory

impairment on an ecologically valid task. The task involved participants having to identify

whether specific electrical appliances were switched on or off, and their spatial location.

Although greater memory impairment is a relatively novel finding the authors attributed it to

the demands placed on the bindings in the executive during encoding, thus supporting the

perspective that memory impairment in OCD is secondary to executive dysfunction.

The current review highlighted the lack of ecologically valid tasks in OCD memory research

but using such tasks are more likely to tap into the specific fears of OCD participants,

heightening their anxiety levels; therefore they may provide more realistic clinical

implications for the understanding and treatment of OCD. The widespread use of

standardised memory measures therefore may not provide a valid and reliable reflection of

memory functioning in OCD, and is an important consideration for future research.

In summary, there is a vast amount of literature into memory impairments in OCD; however,

findings are largely inconsistent. Although nonverbal memory and organisational tasks have

produced largely consistent evidence pointing to a mediating role of organisational strategy

use, the role of organisational strategy use in verbal memory remains unclear. The majority of

studies shared limitations, which may make it difficult to draw absolute conclusions from the

data. Due to the methodological flaws of the studies a number of future research questions

arose - Is reduced organisational strategy use specific to OCD or is it a general function of

anxiety? Can the inconsistencies in research be explained by a lack of ecologically valid

tasks? Would organisational strategy use remain poor if the tasks were idiographically

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designed? Would more consistent findings in relation to memory and organisation be found if

studies employed idiographic stimuli?

Conclusions

A vast amount of research has been conducted into memory performance and OCD, but

findings have been somewhat mixed. Recent reviews have highlighted that such mixed

results may be due to a primary deficit in executive functioning (Greisberg and McKay,

2003), specifically the ability to organise and cluster information (Savage et al, 1998). The

current systematic review aimed to identify and critique the literature specifically addressing

memory and organisational deficits in OCD samples. Possible future directions have also

been discussed for example the importance of including a anxious control group to rule out

the possibility of the impairments being due to heightened anxiety rather than OCD was

identified as a key limitation of the studies reviewed, as well as failing to use idiographic

stimuli to account for the individual nature of OCD and to include memory measures that

have similar demands in order to gain a more direct comparison of verbal and nonverbal

memory. Different findings may be reported if the methodological flaws of the studies are

accounted for and may explain some of the inconsistencies in the literature.

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compulsive disorder. Behaviour, research and Therapy, 34, 633-641.

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Appendix 1

Table 1Nonverbal memory and organisational strategy use in OCD

Author (s) Samples Medication Matching of samples

Nonverbal memory and Organisational strategy tasks15

Nonverbal memory & organisational strategy use

Conclusions

Aycicegi et al (2003)

OCD (n=16)Nonclinical controls (n=15)

No information Age, education (years), socio-economic status, handedness

RBANS – figure copy and recall, list learning, story recall

OCD significant deficits on delayed recall of complex figure

Consistent with the theory that orbitofrontal-limbic system dysfunction underlies OCD

Exner et al (2009)


SSRI (n=6), anti-depressant agents (n=5)

Age, gender, education (years), intelligence

RCFT, CVLT OCD significantly poorer performance on immediate and delayed recall of complex verbal information but not for list learning or complex visual information

Thought-focused cognitive style may influence encoding of complex verbal information

Jang et al (2010)

OCD (n=144)Nonclinical controls (n=144),

SSRI (n=68) Age, socio-economic status

RCFT OCD significantly impaired performance at recall I, recall II and copy organisation

Nonverbal memory deficit related to symmetry/ordering symptoms, organisation deficit related to obsession/checking symptoms

Nedeljkovic OCD (n=59) SSRI (n=41) Gender, age, CANTAB – SWM Checkers – significantly poorer Greater impairments in

15 RBANS – Repeatable Battery for the Assessment of Neuropsychological Status; RCFT – Rey Osterrieth Complex Figure Test; CVLT – California Verbal Learning Test; CANTAB - Cambridge Neuropsychological Test Automated Battery; SWM – Spatial Working Memory task; VLMT – German Verbal Learning Test; TAVEC - Spain-Complutense Verbal Learning Test

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et al (2009) Nonclinical controls (n=59)

education (years) or verbal IQ. OCD matched for medication status, age of onset, length of OCD

performance on spatial working memory tasks

checkers relative to other subtypes, but small effect sizes

Penades et al (2005)


SSRI (n=15) Age, education (years), handedness, verbal IQ, BDI

RCFT OCD – significantly poorer performance on RCFT copy, recall and organisation

Possible that immediate nonverbal memory difficulties are mediated by difficulty in initiating the use of organisational strategies

Rampacher et al (2010)

OCD (n=40) MDD (n=20)Nonclinical controls (n=40)

Excluded if on a dose >0.5mg Benzodiazepines

Native German speakers, gender ratio, education level, medication

RCFT, VLMT OCD significantly poorer perception and manipulation of complex visual information – correlated with OCD symptom severity, OCD significantly poorer performance on visual memory organisational strategy use

OCD patients have difficulty organising and manipulating visual material which are not mediated by depressive symptoms

Savage et al (1999)

OCD (n=20) Nonclinical controls (n=20)

No medication for at least 1 month prior to study

Age, gender, handedness, education, estimated verbal IQ

RCFT OCD - significantly poorer performance in organisational strategy and recollection. Poor recollection was mediated by copy organisational strategies.

Primary deficit found to be in executive functioning, which impacted immediate memory recall.

Savage et al (2000)


SSRI (n=22) Age, education (years)

RCFT, CVLT OCD significantly poorer performance on verbal and nonverbal measures of organisational strategy use and free recall – reduced use of organisational strategies significantly mediated poor free recall for both verbal and nonverbal

Verbal and nonverbal memory difficulties in OCD are related to decreased strategic processing

Segalas et al (2008)


SSRI (n=9)Anti-depressant (n=19)

Age, gender, handedness, education (years)

RCFT, TAVEC OCD significantly reduced immediate and delayed recall as well as recognition of nonverbal material, used less organisational strategies but not significant, significantly reduced

OCD nonverbal recall and recognition Is impaired, whereas for verbal material learning and delayed recall is reduced compared to

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learning and short-term recall of verbal material but no significant difference in use of organisational strategy

nonclinical controls

Shin et al (2004)


SSRI (n=14) Age, gender, RCFT OCD little difficulty in attending to and processing complex visual information but significantly impaired planning and organisation. Significantly poorer recall than copy and persisted when organisation scores excluded

OCD patients have poorer nonverbal memory recall and use of organisational strategies

Simpson et al (2006)

OCD (n=30) Co-morbid OCD (n=15)History of OCD (n=15)Nonclinical controls (n=35)

SSRI (n=23) Age, gender, ethnicity, education (years)

CANTAB – SWM, RCFT

Performance on RCFT comparable to controls, reduced use of organisational deficits but not significant

The difference found may not be specific to OCD. Perhaps only some OCD patients have reduced nonverbal memory and organisational strategy use on the RCFT

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Table 2

Verbal memory and organisational strategy use in OCD

Author(s) Samples Medication Matching of samples

Verbal memory and organisational strategy tasks

Verbal memory and organisational strategy use

Conclusions

Deckersbach et al (2004)

OCD (n=30)BP-I (n=30)Nonclinical controls (n=30)

OCD- SSRI (n=19), BP-I – mood stabilisers (n=24), antidepressants (n=4), antipsychotic meds (n=4)

Age, sex, education (years)BP-I OCD = age of onset, duration of illness

CVLT OCD – significantly impaired organisational strategy use during encoding mediated impaired delayed free recall

Verbal memory impairments in OCD are mediated by difficulties in using organisational strategies during learning

Deckersbach et al (2005)

OCD (n=20)BP-I (n=20)Nonclinical controls (n=20)

OCD – SSRI (n=13)BP-I – mood stabilisers (n=10)

Age, sex, education (years), verbal IQ estimateBP-I OCD = age of onset, duration of illness

Word encoding paradigm task

OCD recall of words comparable to controls. Impaired spontaneous organisation of words, but could organise the words when instructed to do so and informed of the categories

May be a difficulty in spontaneously implementing organisational strategy when encoding information

Sawamura et al (2005)


No information Age, education (years)

Verbal Strategy task adopted from Iddon et al (1998)

OCD - significantly slower to classify words in to semantic categories, significantly poorer recall and recognition of words, used less

Slowness in analysing the features of the word and classifying into semantic categories contributes to impaired memory performance during

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organisational strategy

encoding

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Clinical Experience

Placement: Adult Mental Health Worked within a Community Mental Health Recovery Service (CMHRS). This was a

multi-disciplinary team (MDT), which included Community Psychiatric Nurses (CPN), Psychiatrists and Social Workers. Attended a number of Psychology meetings, CMHRS team meetings and CMHRS business meetings.

Direct work was undertaken with individuals and families and indirect work was undertaken with staff and families. Group work – made adaptations to the current group protocol for CBT for Anxiety and delivered the group with a co-facilitator. The group ran for 8 weeks with a 1-month follow-up session.

Worked with adults with a varied age range (from early twenties to early sixties). Clients were mainly from a White British background – this was reflective of the demographic area of the placement. I also worked with people from White Other background and one client from a Black African background.

Worked with a range of presenting difficulties including – perfectionism, bipolar disorder, obsessive compulsive disorder (OCD), anxiety, depression, post-traumatic stress disorder, panic disorder. Risk assessments completed for new referrals and ongoing risk assessment throughout therapy. Psychological models used for assessment, formulation and intervention included Cognitive Behavioural Therapy (CBT), third wave CBT e.g. mindfulness.

Completed two cognitive assessments with two adults presenting with memory and attention difficulties. These pieces of work involved pre-assessment interviews, administration of a number of psychometric tests, scoring, analysis and interpretation of the results, feedback of results and formulation direct to the clients. The assessments used were the Test of Premorbid Functioning (TOPF), The Wechsler Memory Scale IV (WMS-IV), Wechsler Adult Intelligence Scale IV (WAIS-IV), the Test of Everyday Attention, Trails Making Test (TMT) and the FAS verbal fluency test.

Other assessment measures used throughout the placement: Penn State Worry Questionnaire, Dysfunctional Attitude Scale, Generalised Anxiety Disorder Scale, Padesky Anxiety Inventory, CORE-OM, and CORE Goal Attainment Form.

Continuing Professional Development (CPD) – Personality Disorders, CBT for Psychosis – each were one full day.

Presentation to an external staff team on the Five Ways to Wellbeing model. Service Development & Evaluation: Designed a poster to promote the carer’s group and a

leaflet to promote the CBT for Anxiety group. Completed a service evaluation of the CBT for Anxiety group.

Placement: Learning Disabilities

Worked within a community team for people with learning disabilities (CTPLD). This was a MDT that consisted of CPN’s, Psychiatrists, Speech and Language Therapists (SLT), Occupational Therapists (OT) and Art Therapists. Attended a number of meetings – risk meetings, CPA discharge meetings, forensic team meeting,

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psychology team meetings, CTPLD meetings and business meetings, as well as the LD Partnership board meeting.

Direct work with individual and families and indirect work with staff teams and families. Worked with adults with a varied age range (from late teenage years to early sixties). Group work – Keeping safe in relationships. This was an 8-week group with an individual follow-up session. The group was based on CBT and psychoeducation. Worked with adults from a diverse range of cultural and religious backgrounds. Other diversity issues included diagnosis of a LD, genetic syndromes and receptive and expressive communication difficulties.

Worked with a range of presenting difficulties including anger management, emotion regulation, attachment difficulties, anxiety and relationship. Risk assessments completed for new referrals and ongoing risk assessment throughout therapy. Psychological models used for assessment, formulation and intervention included CBT, third wave CBT e.g. mindfulness, and behaviour therapy. Formulations were also informed by psychodynamic and systemic schools of thought.

Various assessments were completed: Assessment of sexual knowledge and understanding. This involved completing the Brook Advisory Centre “Not a Child Anymore”, BILD “Exploring Knowledge and Understanding”. Assessment of dementia for a client with Downs Syndrome. This involved the following assessments – Neuropsychological Assessment of Intellectual Disability, CAMCOG-LD, British Picture Vocabulary Scale (BPVS), accessible interview, Carers interview. Assessment of Asperger’s Syndrome in the context of a history of police involvement. This involved the following assessment means - WAIS-IV, interview schedules and the SMAT. Impact of moving assessment for a long-term residential client whose secure home was closing. This involved extensive file history review, discussion with carers and attendance at meetings. Assessments of behaviour that challenges others. These pieces of work involved interviews with families and carers, observations in a range of settings, the Functional Assessment Interview (FAI), Challenging Behaviour Interview, questionnaires relating to the staff beliefs on behavior motivation and management.

Cognitive assessment completed to inform future housing needs in light of cognitive profile. This involved the following assessments - WAIS-IV, Rivermead Behavioural Memory Test 3, Trails Making Test (TMT) and the Behavioural Assessment Dysexecutive Syndrome.

Consultation work – assessment, formulation and consultation work to team planned but to be delivered by supervisor due to placement ending. Joint consultation work with a SLT to another staff team

CPD: attended the SABP LD Conference – one full day conference on the response to Winterbourne View. Key discussions focused on government issues, challenging behavior and medical perspectives.

Presentation to a staff group on the Experiences of being a First Year Trainee Clinical Psychologist.

Service development: designed an accessible leaflet for service users to help them understand the referral process into the CTPLD.

Placement: Older People

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Worked within a MDT that included Social Workers, OTs, community nurses and Psychiatrists. Attended a number of psychology team and CPD meetings.

Undertook direct work with individuals and indirect work with staff teams. Co-facilitated a cognitive stimulation therapy group for people with a diagnosis of dementia. Also adapted a leaflet for this group. Worked with clients with a varied age range (from mid-sixties to late nineties). Clients were from a diverse range of cultural and religious backgrounds and one piece of work involved working with an interpreter.

Worked with a range of presenting difficulties including panic, hoarding, depression, OCD and dementia (various types). Worked with a number of clients around behavior that challenged others. Many clients had a diagnosis of memory impairment or suspected memory impairment. Psychological models used for assessment, formulation and intervention included CBT, narrative therapy, behavioural therapy, Newcastle model of challenging behaviour and cognitive stimulation therapy. Formulations were informed by other schools of thought such as systemic and psychodynamic models.

Provided supervision to two assistant psychologists. Cognitive assessment for suspected dementia. The following assessments were used –

TOPF, WAIS-IV, WMS-IV, Hopkin’s Verbal Learning Test, TMT, the Hayling and Brixton assessment, Geriatric Depression Scale and the Hospital Anxiety and Depression Scale.

Other assessments used on this placement were: Addenbrookes Cognitive Examination III, challenging behavior interviews, Obsessive Compulsive Inventory Revised, Savings Inventory and the Yale Brown Obsessive Compulsive Scale.

CPD: neuropsychological case discussion and reformulation, Acceptance and Commitment Therapy for Psychosis in Older People and working with physical health conditions and health anxiety.

Presentation completed on Health Anxiety to other Psychologists.

Placement: Child

Worked within a Community Adolescent Mental Health Service and a Children’s and Young Persons Learning Disability Team (CYPS-LD). The teams were multidisciplinary and included Psychiatrists, Community Nurses and Social Workers.

Attended a number of psychology team meetings, CAMHS assessment clinic and CBT consultation groups.

Direct work was undertaken with individuals and families and indirect work was undertaken with staff and families. Group work – co-facilitated a Healthy Thinking group with two other professionals. The group ran for 6 weeks with a 1-month follow-up session. The group was based on the CBT model for anxiety and depression.

Worked with children aged six years and upwards, and were from a diverse range of cultural and religious backgrounds. Other diversity issues included the diagnosis of a LD, autistic spectrum conditions, and receptive and expressive communication difficulties.

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Worked with a range of presenting difficulties including –anxiety, depression, paranoia and psychotic experiences, self-harm, OCD, selective mutism, and behaviour that challenges others. Risk assessments completed for new referrals and ongoing risk assessment throughout therapy. Psychological models used for assessment, formulation and intervention included CBT, narrative techniques, systemic and behavioural models.

Consultation work completed to own team on a specific client. Completed two cognitive assessments – one querying the diagnosis of a LD, and one

to inform support needs. The following assessments were used for these pieces of work – Wechsler Intelligence Scale for Children IV, Children’s Memory Scale, Leiter Performance Scale, and the BPVS.

Other standardised assessments used throughout the placement included the GAD7, Strengths and Difficulties Questionnaire, Sheffield Learning Disabilities Outcome Measure, Birlesden Depression Scale and Spence Anxiety Scale.

Service development – mapping outcome measures to specific care pathways within the CYPS-LD service.

CPD: Mindfulness training day (two full days). I also attended the STARS training which focused on the needs and well-being of young people affected by sexual abuse.

Presentation to the CYPS-LD team on the importance of using outcome measures and provided feedback on national agendas.

Placement: Specialist – Pediatric neurorehabilitation Worked with a specialist pediatric neurorehabilitation service. The team included

Psychiatrists, nurses, Health Care Assistants, Social Workers, SLTs, OTs, Physiotherapists, Educational Psychologists and teachers.

Attended a psychology meeting, a research day and various client focused meetings at various time points during their rehabilitation placement.

Direct work was undertaken with individuals and families as was indirect work. Indirect work was also undertaken with the staff team. Group work – developed and co-facilitated a Siblings group and a parent workshop.

Worked with children aged 7 and upwards, and were from a range of diverse cultural and religious backgrounds. All children had an acquired brain injury.

Worked with a range of presenting difficulties including anxiety, managing relationships, loss and adjustment and behaviours that challenge. Risk assessments completed for new referrals and ongoing risk assessment throughout therapy. Psychological models used for assessment, formulation and intervention included CBT, narrative techniques, systemic and behavioural models. Formulation was heavily informed by neurodevelopmental models, individual and family life cycle, Bronfenbrenner’s eco-systems theory and the WHO-ICF model of disability.

Formal and informal consultation work completed with the staff team. Standardised cognitive assessment was difficult to undertake as the clients worked

with presented with severe receptive and expressive communication difficulties, therefore other specialties completed this where possible.

For behaviour that challenged others, the work involved direct observations, interviews with parents and staff team, the completion of the FAI and the Motivation Behaviour Scale.

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Other measures used throughout the placement included the HADS and the four field map, as well as home grown measures by the psychology team.

Service development: Developed a siblings group, made adaptations to a parent workshop, and developed a leaflet aimed at parents supporting their child. Jointly wrote two blog posts for the intranet.

CPD: BPS event held at the University of Surrey – focused on Addictions. This related to the placement as it informed our assessment of parental coping at admission and ongoing throughout their child’s rehabilitation.

Presentation: Jointly presented to parents on brain injury education and common dilemmas parents can face in the context of their child acquiring a brain injury. Case presentation for psychosocial team developed.

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Assessments

Year I Assessments

PROGRAMME

COMPONENT

TITLE OF ASSIGNMENT

Fundamentals of Theory

and Practice in Clinical

Psychology (FTPCP)

Short report of WAIS-III data and practice

administration

Research –SRRP A service evaluation of a Cognitive Behavioural

Therapy group for anxiety in a CMHRS

Practice case report An assessment and formulation based on Wells (1999)

cognitive model for an adult woman presenting with

Generalised Anxiety Disorder

Problem Based Learning

– Reflective Account

Problem Based Learning - The relationship to change

Research – Literature

Review

Are memory difficulties in OCD primarily due to

organisational deficits during encoding of information?

Adult – case report Cognitive Behavioural Therapy with an adult woman

presenting with anxiety

Adult – case report CBT for Anxiety group in an Adult Mental Health

CMHRS

Research – Qualitative

Research Project

The Experience of Being a First Year Trainee Clinical

Psychologist

Research – Major

Research Project

Proposal

MRP Proposal - An investigation of verbal and

nonverbal memory deficits in OCD whilst controlling

for spontaneous organisational strategy use and state

anxiety

Year II Assessments

PROGRAMME

COMPONENT

TITLE OF ASSESSMENT

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Research Research Methods and Statistics test

Professional Issues

Essay

Advances in medical care mean that people with learning

disabilities are living much longer lives. What are some

of the challenges for older people with learning

disabilities and their carers? What is the role of a clinical

psychologist in supporting them with these challenges?

Problem Based

Learning – Reflective

Account

Problem based Learning – Reflective Account

People with Learning

Disabilities/Child and

Family/Older People –

Case Report

Functional analysis of a referral for “challenging

behaviour” with a lady with severe learning disabilities

and living in a medium-secure setting, and planned

follow-up consultation

Personal and

Professional Learning

Discussion Groups –

Process Account

Process account of Personal and Professional Learning

Discussion Groups

People with Learning

Disabilities/Child and

Family/Older People –

Oral Presentation of

Clinical Activity

My development and experience of providing supervision

to an Assistant Psychologist during my Older People

clinical placement

Year III Assessments

PROGRAMME

COMPONENT

ASSESSMENT TITLE

Research – MRP

Portfolio


The Impact of Spontaneous Organisational Memory

Strategy Use and Anxiety on Memory Performance and

Metamemory

Personal and On becoming a clinical psychologist: A retrospective,

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Professional Learning –

Final Reflective

Account

developmental, reflective account of the experience of

training

Child and

Family/People with

Learning Disabilities/

Older People/Specialist

– Case Report

Assessment of a Learning Disability for a Teenage Boy

with ADHD

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epubs.surrey.ac.ukepubs.surrey.ac.uk/808903/15/EThesis_6154083.doc · Web viewIntegrating such theories into treatment models may help to further understand OCD from both clinician