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SUBCLINICAL PSYCHOPATHYAND EMPATHY

Bachelor Degree Project in Cognitive NeuroscienceECTS 15Spring term 2013

Björn Persson

Supervisor: Stefan BerglundExaminer: Daniel Broman

SUBCLINICAL PSYCHOPATHY AND EMPATHY 2

Subclinical Psychopathy and Empathy

Submitted by Björn Persson to the University of Skövde as a final year project towards

the degree of B.Sc. in the School of Humanities and Informatics. The project has been

supervised by Stefan Berglund.

12 June, 2013

I hereby certify that all material in this final year project which is not my own work

has been identified and that no work is included for which a degree has already been

conferred on me.

Signature:


Abstract

Psychopathy is a severe personality disorder that results in antisocial, manipulative,

and callous behavior. The main diagnostic instrument for assessing psychopathy is the

Psychopathy Checklist-Revised. This thesis will introduce the psychopathy construct,

including what is known as subclinical psychopathy. Subclinical psychopathy refers to

individuals who exhibit many of the characteristics of psychopathy, except for some of

the more severe antisocial behaviors. This constellation of traits allows the subclinical

psychopath to avoid incarceration. The fundamental difference between clinical and

subclinical psychopaths is a major question in the field of psychopathy and is the main

theme of this thesis. Impaired empathy is one of the key aspects of psychopathy and it

may be a significant factor in both clinical and subclinical psychopaths. Subclinical

psychopathy may be related to a moderated or altered expression of empathy. Hence,

the empathy construct is a secondary concern in this thesis. This thesis has two aims:

(a) to argue that the conceptualization of subclinical psychopathy is flawed and needs

revision in accordance with less ambiguous criteria; and (b) to present data in support

of the hypothesis that subclinical psychopaths have intact, or even enhanced, cognitive

capacities in contrast to clinical psychopaths.

Keywords: psychopathy, clinical psychopathy, subclinical psychopathy, cognitive

empathy, affective empathy


Table of Contents

Abstract 3

Introduction 5

Clarifying the Psychopathy Construct 7

Antisocial Personality Disorder . . . . . . . . . . . . . . . . . . . . . . . . . . 7

The Psychopathy Checklist . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Gender Differences in Psychopathy . . . . . . . . . . . . . . . . . . . . . . . . 11

Clinical and Subclinical Psychopathy 13

Subclinical Psychopathy as a Manifestation of the Disorder . . . . . . . . . . . 14

Subclinical Psychopathy as a Moderated Expression of the Full Disorder . . . . 15

Subclinical Psychopathy from a Dual-Process Perspective . . . . . . . . . . . . 15

Empathy 17

Cognitive and Affective Empathy . . . . . . . . . . . . . . . . . . . . . . . . . 18

Motor Empathy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Empathizing–Systemizing Theory . . . . . . . . . . . . . . . . . . . . . . . . . 22

The Neurophysiological Basis of Psychopathy 26

Structural Deficits and Abnormalities in Psychopaths . . . . . . . . . . . . . . 26

Amygdala . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Prefrontal cortex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Temporal lobe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Hippocampus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Corpus callosum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Neuroimaging and Empathy . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Discussion 31

References 38


Subclinical Psychopathy and Empathy

Psychopathy is a severe personality disorder characterized by self-centeredness,

callousness, and a profound lack of empathy, which hinders the individual to form

warm emotional relationships with others (Hare, 1999b). The psychopathy construct

is a complex issue, and even amongst professionals there remains doubt as to what a

valid, working description of psychopathy really encompasses (Hare & Neumann,

2006; Skeem, Polaschek, Patrick, & Lilienfeld, 2011). In 1941, Hervey Cleckley

published the first edition of The Mask of Sanity, which became a milestone in the

field. Cleckley presented a description of the typical psychopath by the use of

countless clinical observations of adult male patients categorized as “psychopathic”.

Cleckley (1941/1988) introduced 16 characteristics distinguishing the psychopath:

superficial charm, absence of delusions, absence of nervousness or psychoneuroticism,

unreliability, insincerity, lack of remorse, antisocial behavior, poor judgment,

pathologic egocentricity and incapacity for love, lack of affect, specific loss of insight,

unresponsiveness in interpersonal relations, fantastic and uninviting behavior, suicides

rarely carried out, impersonal sex life, and failure to meet life plans.

These criteria were used as a starting point for Robert D. Hare during the

creation of the Psychopathy Checklist (PCL; Hare, 1985) and in the subsequent

development of the Psychopathy Checklist-Revised (PCL-R; Hare, 1991, 2003). The

PCL-R has since become the premier assessment instrument in the area of psychopathy

(Patrick, 2006). In contrast to the PCL-R, the current edition of the Diagnostic and

Statistical Manual of Mental Disorders (American Psychiatric Association [APA], 2000)

equates psychopathy with the term antisocial personality disorder (ASPD), which has

sparked controversy because such a distinction inevitably creates unnecessary

construct ambiguity (Hare, 1996; Hare & Neumann, 2006).

The public image of a psychopath is very broad, including conceptions such as

the corporate psychopath, the manipulative boss who achieves what he wants at any

cost. The con artist, the charismatic, and highly intelligent individual with

chameleon-like qualities. The chronic offender, who from an early age is burdensome


to society by causing all sorts of trouble, perpetually coming and going to and from

detention centers, and later in life, prisons; and the serial killer. These descriptions

overlap in part, but they are also very distinct (Skeem et al., 2011). Psychopathy is

dissociable from violence, but the key measure of psychopathy, namely the PCL-R

(Hare, 2003), contain items that predict violence.

The main focus of this thesis is subclinical psychopathy, or what is sometimes

referred to as successful psychopathy. The subclinical psychopath is described as an

individual that embody most of the psychopathic behaviors, but refrains from serious

antisocial traits, and is therefore rarely imprisoned or institutionalized (Hall &

Benning, 2006). The term has its root in Cleckley’s previously mentioned book, which

described individuals that had the essential characteristics of a clinical psychopath, but

without behaving in a way that led to frequent arrests or convictions (Cleckley, 1988).

Current research suggests that the subclinical psychopath, like the clinical psychopath,

is devoid of affective empathy (Gao & Raine, 2010), which is a related concern in this

thesis. Relatively little empirical research has been conducted on subclinical

psychopathy (Hall & Benning, 2006), but when the material permits, the two groups

will be contrasted.

This thesis first outlines psychopathy as a construct and its relation to ASPD.

Second, there is a brief overview of the conceptual frameworks regarding the

differences between the clinical and subclinical psychopath. Third, an outline of the

empathy construct and its relation to psychopathy is presented. Lack of affect is a

significant part of the psychopathy construct, and empathy is therefore a relevant and

related construct. Fourth, empirical evidence pertaining to both empathy and

psychopathy will be reviewed, which includes subsequent discussion regarding the

state of the psychopathy construct. The main argument presented in this thesis

concerns the conception of subclinical psychopathy, and it is argued that the current

conception is problematic in several different ways. The conclusion states that the

conception of subclinical psychopathy needs revision in terms of more objective

criteria.


Clarifying the Psychopathy Construct

Antisocial Personality Disorder

ASPD was first introduced in the third edition of the DSM (DSM-III; APA, 1980),

and contrary to both Cleckley’s and Hare’s criteria of psychopathy, the DSM relied

solely on behavioral characteristics (e.g. aggressive outbursts and impulsivity) rather

than affective or interpersonal traits, such as: egocentricity, deceit, shallow affect,

manipulativeness, selfishness, and lack of empathy, guilt or remorse; which have been

key in the conceptualization and diagnosis of psychopathy (Hare, 1996).

The DSM-IV-TR (APA, 2000), describes an individual with ASPD as someone

with: “a pervasive pattern of disregard for, and violation of, the rights of others that

begins in childhood or early adolescence and continues into adulthood. This pattern

has also been referred to as psychopathy, sociopathy, or dyssocial personality disorder.”

(pp. 701-702). (Complete diagnostic criteria are available in Table 1.) It is important

to note that the quite rigid terminology of the DSM-IV-TR is not necessarily a rule of

law within contemporary psychiatry. For instance, DeWall and Anderson (2011)

defines antisocial behavior via reference to actions that violate personal or cultural

standards for appropriate behavior. Thus, antisocial behavior often encompasses

violence and aggression, but it also includes behavior such as cheating, stealing and

breaking other laws. This clarification does not make a very significant difference in

relation to subclinical psychopathy. The subclinical psychopath is not necessarily

devoid of antisocial behavior as such, but rather of the more severe antisocial traits

(LeBreton, Binning, & Adorno, 2006).

According to DSM-IV-TR (APA, 2000) psychopathy and ASPD can be considered

synonymous constructs, which has since been a point of controversy (Hare &

Neumann, 2006). Personality traits were deemed too difficult for clinicians to gauge,

and were therefore disqualified from the ASPD diagnosis (Hare, 1996; Hare &

Neumann, 2006). Hare has argued that the creation of ASPD resulted in an entirely

new construct which is related to – but not synonymous with – psychopathy, as

measured by the PCL-R (Hare & Neumann, 2006). The evidence to support this claim


Table 1

Diagnostic criteria for antisocial personality disorder (DSM-IV-TR)

A) There is a pervasive pattern of disregard for and violation of the rights of othersoccurring since age 15 years, as indicated by three or more of the following:

1. failure to conform to social norms with respect to lawful behaviors asindicated by repeatedly performing acts that are grounds for arrest;

2. deception, as indicated by repeatedly lying, use of aliases, or conningothers for personal profit or pleasure;

3. impulsiveness or failure to plan ahead;4. irritability and aggressiveness, as indicated by repeated physical fights or

assaults;5. reckless disregard for safety of self or others;6. consistent irresponsibility, as indicated by repeated failure to sustain

consistent work behavior or honor financial obligations;7. lack of remorse, as indicated by being indifferent to or rationalizing having

hurt, mistreated, or stolen from another;B) The individual is at least age 18 years.C) There is evidence of conduct disorder with onset before age 15 years.D) The occurrence of antisocial behavior is not exclusively during the course of

schizophrenia or a manic episode.

can be found in forensic populations, in which there is an asymmetric association

between ASPD and PCL-R, that is to say, most inmates that score high on the PCL-R

meet the criteria for ASPD, but most with high scores of ASPD do not meet the criteria

for PCL-R psychopathy (Hare, 1996; Hare & Neumann, 2006).

The prevalence of psychopathy in the general public is a much debated issue.

Hare (1999a) estimated that the prevalence rates are around 1%. Blair, Mitchell, and

Blair (2005) has estimated that the prevalence of psychopathy .75% in the general

population. The authors do not specify in which part of the world these measurements

were carried out. This is significant because there are cultural differences in the

prevalence of psychopathy traits (Cooke, 1998), however, details in regards to that

subject is beyond the scope of this thesis. Furthermore, Blair et al. (2005) inferred

their results from the prevalence rates of ASPD, which in turn has been estimated at a

rate of 3% in the general population (APA, 2000), and 50-80% in prison populations

(Ogloff, 2006). Coid and colleagues (2009) conducted a study which estimated that

the prevalence rate of psychopathy in Great Britain is 0.6% (95% CI: 0.2–1.6).


There are a number of difficulties with providing an exact prevalence rate. One

such difficulty is that psychopaths are almost exclusively studied inside prisons.

Psychopathy is also much more frequent in prison populations (about 25%) than in

the general population, thus making the numbers difficult to generalize from one

paradigm to another (Hare, 1996; Hare & Neumann, 2006). Furthermore, the

difficulties surrounding the construct have led to dubious data regarding prevalence

rates. The studies of psychopathy prevalence in prison populations have varied

depending on the cut-off score used on the PCL-R questionnaire. Thus, it has been

argued that the cut-off score has an element of arbitrariness, and is essentially as good

as the knowledge and ability of the researcher (Blackburn, 2009).

Rogers, Salekin, Sewell, and Cruise (2000) had the following comment on the

construct validity issue: “DSM-IV does considerable disservice to diagnostic clarity in

its equating of A[S]PD to psychopathy” (p. 237). Further, they argued that the

intermittent changes in ASPD shatter any illusion of a possibility of a unitary

diagnosis. The relationship between ASPD and PCL-R psychopathy is still under

dispute (Coid & Ullrich, 2010; Hare, 1996, 2003; Hare & Neumann, 2006, 2008).

Recently, Coid and Ullrich (2010) hypothesized that ASPD and psychopathy

belong on the same continuum because they may share etiology. The researchers were

unable to show that ASPD and psychopathy are distinct diagnostic entities, and

accordingly, they found no evidence to suggest that individuals with both ASPD and

psychopathy constitute a specific subcategory. Instead they suggested that psychopathy

is too complex to measure dichotomously, based on an arbitrary cut-off point.

The Psychopathy Checklist

Robert D. Hare created a diagnostic tool (the PCL) which corresponds more

closely to Cleckley’s original definition of psychopathy (Hare, 1996; Hare & Neumann,

2006). Originally, Hare and his colleagues rated prison inmates along a 7-point (low

to high) rating scale based on Cleckley’s criteria for psychopathy. This yielded over

100 items, some of which were deemed too vague or difficult to score. A series of

subsequent statistical analyses determined which items had the best psychometric


properties. These items were used in the original PCL questionnaire, which consisted

of 22 items. Each item was measured on a three point (0, 1, 2) ordinal scale, where 0

indicated that the characteristic was not present or did not apply, 1 indicated

uncertainty as to whether it applied or not, and 2 indicated that the characteristic was

definitely present. Each item is scored on the basis of an interview and file

information, which is the standard PCL procedure (Hare & Neumann, 2006).

Over the years, the PCL has been subject to minor revisions, including the

removal of two items due to scoring difficulties and reliability issues. The current (2nd)

edition of the PCL-R (Hare, 2003), contains 20 items (See Table 2), yielding a

maximum score of 40, with a cut-off score typically set to 30 (Hare & Neumann,

2005). The cut-off score is generally adjusted depending on the purposes of the

procedure (e.g., research, forensic, or risk assessment). Adjusting the cut-off scores

has been seen as problematic, because it potentially renders the PCL-R measurements

arbitrary (Leygraf & Elsner, 2008). In order to understand any psychological

construct, a clear underlying dimensionality needs to be developed.

In the case of psychopathy, recent exploratory factor analytic research has shown

that between two to five factors (Cooke & Michie, 2001; Hare, 2003; Hare et al.,

1990; Hare & Neumann, 2008; Widiger & Lynam, 1998) can be amassed from

psychopathy measurements (Hare & Neumann, 2006). There is an ensuing debate as

to whether or not psychopathy is a unitary or multifarious construct or in other words,

if there is a single underlying etiology or multiple etiologies (Lilienfeld & Fowler,

2006; Skeem et al., 2011).

Most researchers adhere to a two-factor model (viz. interpersonal-affective and

social deviance) which divides into four facets (viz. interpersonal, affective, lifestyle,

and antisocial), but whether or not the factors diverge in different directions has been

called into question (Skeem et al., 2011). There is some evidence that the two major

factors (i.e., interpersonal-affective, and social deviant) correlate to external variables

in different directions. An example of this is that the interpersonal factor is negatively

associated with emotional distress, and the social deviance factor is positively


Table 2

Psychopathy Checklist–Revised (PCL-R) Factors, Facets, and Items

Factor 1: Interpersonal-affective scale Factor 2: Social deviance scale

Facet 1Interpersonal

Facet 2Affective

Facet 3Lifestyle

Facet 4Antisocial

Glibness or super-ficial charm;Grandiose senseof self-worth;Pathological lying;Conning or ma-nipulative

Lack of remorseor guilt;Shallow affect;Callous or lack ofempathy;Failure to acceptresponsibility

Need for stimula-tion;Parasitic lifestyle;Lack of realisticlong-term goals;Impulsivity;Irresponsibility

Poor behavioral con-trols;Early behavioral prob-lems;Juvenile delinquency;Revocation of condi-tional release;Criminal versatility

From (Hare, 2003)Note. Two PCL-R items are not included in this factor structure: namely “promiscuoussexual behavior”, and “many short-term marital relationships”, because they do notload onto any specific factor (Hare & Neumann, 2006). Hare and Neumann (2008)refer to this model as a two factor higher-order representation of a four factorcorrelated model.

associated with emotional distress (Hicks & Patrick, 2006). This aspect of the

construct has not been conclusively proved either way, thus the field remains divided

(Skeem et al., 2011).

Gender Differences in Psychopathy

Gender differences in psychopathy will generally not be taken into account in

this thesis, in large part due to that the overwhelming majority of empirical research

has been on male offenders and psychiatric patients. However, there are a few

interesting differences that relate to subclinical psychopathy and problems with

assessment. One of these issues is the prevalence of psychopathy in women, which has

been estimated (in prisons and institutions) at 9% to 23% in women, compared to

15% to 30% in men (Nicholls, Ogloff, Brink, & Spidel, 2005; Vitale, Smith, Brinkley, &

Newman, 2002). The relatively high percentage span is because measurements were

made in different cultures, in which different cut-off scores are utilized for reasons

that are beyond the scope of this thesis (Logan & Weizmann-Henelius, 2012).


Another gender related issue regarding psychopathy is that women tend to

present with slightly different characteristics than men. The stereotypical gender roles

of men and women tend to be amplified in psychopaths. This means that psychopathic

men are more physically aggressive, dominant, are less anxious and emotional.

Psychopathic women are to a lesser extent physically violent, but instead rely more on

relational aggression (including child abuse and sexual coercion). Emotionally,

psychopathic men and women are believed to be very similar, with the difference

being that women are more emotionally unstable and anxious (Logan &

Weizmann-Henelius, 2012).

Hare (2003) argued that it is likely that the PCL-R score represents much the

same level of psychopathy in both male and female psychiatric patients and offenders.

This assumption may be erroneous, because the behavior related to the antisocial

items (Facet 4) may present more infrequently in women (Logan &

Weizmann-Henelius, 2012). Women also have a lower rate of criminal convictions and

reconvictions (Forouzan & Cooke, 2005; Gelsthorpe, 2004; Verona & Vitale, 2006),

which is interesting in relation to subclinical psychopathy, and especially in regards to

the criticism portrayed in this thesis.

Psychopathic women are also reported to be more flirtatious. More specifically, it

has been reported that they are charmed by the psychiatrist performing the PCL-R

interview, whereas psychopathic men tend to try to impress and charm the interviewer

(Forouzan & Cooke, 2005). Applying the PCL-R criteria to women may also have the

disadvantage of inferring behavior that has different social and psychological meaning

for men and women. One such example relates to sexual promiscuity, which in

psychopathic women may relate to manipulation and securing partners one can

exploit; the same criteria in psychopathic men on the other hand, may relate more to

sensation- or status-seeking efforts (Quinsey, 2002).

The PCL-R manual lack guidance when it comes to interpreting some of the items

in relation to women. For instance, the item parasitic lifestyle is ambiguous, because

women have a material and financial dependency on men to a larger extent than the


reverse scenario. In many societies, this is a social norm that is broadly accepted. The

opposite is not broadly accepted, and therefore, male financial dependency on women

is sometimes interpreted as parasitic behavior (Logan & Weizmann-Henelius, 2012).

The various facts mentioned here has led some researchers to conclude that gender

equivalence in the expression of psychopathy cannot be assumed (Forouzan & Cooke,

2005), which in turn may have a significant effect on prevalence scores, both in the

community and in forensic settings (Logan & Weizmann-Henelius, 2012).

Clinical and Subclinical Psychopathy

The subclinical psychopath is defined by the quite blunt criterion of whether or

not the individual has been imprisoned or institutionalized. Practically, the difference

between the clinical and subclinical psychopath is a behavioral one. The subclinical

psychopath is engaged in behaviors that breach social norms – but are not necessarily

illegal – such as achieving personal or professional success at the expense of others,

which is why the term successful psychopathy is often employed as a synonym (Hall &

Benning, 2006). There are two important caveats that need mentioning: first,

subclinical psychopaths are considerably less antisocial than the clinical psychopath,

but this does not mean that they are always non-violent. Second, the clinical or

unsuccessful psychopath is not defined simply by where the individual is currently

located, but rather by looking at criminal history etc. Thus, a psychopath that has

been convicted of several crimes, but is currently residing in the community is not

considered a successful psychopath (Gao & Raine, 2010).

There are several difficulties with studying subclinical psychopathy. First, it has

been argued that the focus on antisocial behavior in DSM-III, and DSM-IV have led to

an under-representation of other behaviors, and traits (Lilienfeld, 1998; Messick,

1995). Second, identifying subclinical psychopaths has proven a difficult task. Third,

the PCL-R was developed primarily based on data from incarcerated inmates (Hare,

Clark, Grann, & Thornton, 2000), and this data may not generalize onto psychopaths

(either clinical or subclinical) residing in the community (Hall & Benning, 2006).


Additionally, another difficulty relates to the screening of psychopaths in

subclinical environments, being that the PCL-R employs a semi-structured interview

and inmate conviction history etc. This level of rigor in screening procedure is not

possible in the general population (Hall & Benning, 2006). This led to the creation of

alternative instruments, such as the Psychopathic Personality Inventory (PPI; Lilienfeld

& Andrews, 1996). These are some of the reasons for the low output of studies

regarding subclinical psychopathy (Hall & Benning, 2006).

At least three important reasons have been proposed for studying the clinical and

subclinical psychopaths (Gao & Raine, 2010). First, the fact that an overwhelming

majority of the research on psychopathic individuals has been based on clinical

psychopaths means that the collected data may not generalize to subclinical

psychopaths. This is very important because, as stated previously, the prevalence of

psychopathy is estimated at around 0.6-1% in the general population (Coid, Yang,

Ullrich, Roberts, & Hare, 2009; Hare, 1999a) and 3.5% in the business world (Babiak

& Hare, 2009). Thus, subclinical psychopaths may outnumber clinical psychopaths.

Second, studying subclinical psychopaths may lead to etiological insights, and they

may function as a “control group”, in the sense of excluding, or diminish criminality as

a criterion. Third, the etiology of subclinical psychopathy may be different from

clinical psychopathy, and the factor, or factors that shield the subclinical psychopath

from incarceration may be relevant for rehabilitation and proactive purposes (Gao &

Raine, 2010). Researchers disagree about how the clinical and subclinical aspects of

psychopathy can converge. Hall and Benning (2006) have provided descriptions of the

three main conceptual perspectives.

Subclinical Psychopathy as a Manifestation of the Disorder

Subscribers of this perspective argue that the same etiological differences can be

found in the subclinical psychopath, but at reduced severity, in comparison to the

clinical psychopath (Hall & Benning, 2006). Gustafson and Ritzer (1995) argue that

clinical and subclinical psychopaths differ only in degree, not in type. Their research

rebranded the subclinical psychopath as an aberrant self-promoter which is


conceptualized as an individual that is exploitative, lack empathy, violate social norms,

and have highly narcissistic behavior, although the ASP’s behavior need not technically

be illegal. The purpose of this distinction is to find patterns between individuals who

are not necessarily psychopaths according to the PCL-R, and yet are socially

destructive in their everyday lives.

Subclinical Psychopathy as a Moderated Expression of the Full Disorder

This approach proposes that clinical and subclinical psychopaths share not only a

common etiology but also equivalent severity of the basic underlying pathology.

Lykken (1995) proposed that some of the heroes, leaders and adventurers of a society

have the same predisposition to fearlessness that can be found in psychopaths. Albeit,

with the difference of having an adequate level of socialization during their

upbringing, thus ridding them of antisocial behavior. The theory suggests that

expression of antisocial behavior may be reduced if an individual has compensatory

factors, such as a special talent, high intelligence, high socioeconomic status etc. (Hall

& Benning, 2006).

Subclinical Psychopathy from a Dual-Process Perspective

In this conceptualization, the interpersonal–affective features of psychopathy are

considered to be etiologically distinct from the antisocial behavior component, it has

been referred to as the dual-process, or dual-deficit model of psychopathy (Fowles &

Dindo, 2006). Being that these two trait dimensions are thought to reflect distinct

etiologies, certain individuals could exhibit an elevation in one dimension but not the

other (Hall & Benning, 2006). Thus, the subclinical psychopath would have elevated

levels of interpersonal-affective traits, but have about normal levels of traits related to

antisocial deviance. This model draws inspiration from the two factor model of

psychopathy, which in this framework allows for the possibility of diverging behavior,

which allows the possibility of scoring high on one factor, but low on the other.

Accordingly, if one scored high on the interpersonal-affective factor, but not the

antisocial factor, one would perhaps fit into this conception of subclinical psychopath

(Hall & Benning, 2006). It should be noted that the three distinctions presented here


are not necessarily mutually exclusive, but rather, different approaches to the same

problem (Hall & Benning, 2006). Furthermore, the first and second perspectives can

be interpreted as advocating that the psychopathy construct belongs on a spectrum,

whereas the third perspective argues that there is a difference in etiology between the

two groups.

These three conceptualizations are interesting in relation to current research. For

instance, Gao and Raine (2010) postulated that the subclinical psychopath is

successful because of a number of factors: “. . . intact or enhanced neurobiological

processes, including better executive functioning, increased autonomic reactivity,

normative volumes of prefrontal gray and amygdala, and normal frontal functioning”

(p. 194), which may serve as “. . . factors that protect successful psychopaths from

conviction and allow them to attain their life goals, using more covert and nonviolent

approaches” (p. 194). Surprisingly little has been said about these matters, that is,

what makes the successful psychopath successful. A skeptic could argue that

imprisonment is an arbitrary point of measure when it comes to such things as

behavior and personality, because imprisonment is in part dependent on culture,

socioeconomic status, skin color, age, etc. In other words, the skeptic would appeal to

a stronger conceptualization that utilizes something like biological or neuronal

empirical data.

Gao and Raine (2010) comment that serial killers who evade justice for a very

long time, but eventually get caught, could constitute a form of “semi-successful”

psychopathy. One could argue that such a conceptualization goes against all three

perspectives, because all three attempt to retain that subclinical psychopaths are not

as severely antisocial as clinical psychopaths. Serial killers constitute the very epitome

of severe antisocial behavior, and thus, calling them semi-successful yields serious

consequences for the traditional notions of a subclinical psychopath.


Empathy

In Cleckley’s (1988) original description of the psychopath, a key characteristic

was lack of remorse, and a poverty of emotional reactions. This notion has since

become a major part in the psychopathy construct (Baron-Cohen, 2012; Blair, 2005;

Hare, 1999b, 2003). Empathy has been defined by Baron-Cohen (2012) in the

following way: “Empathy is our ability to identify what someone else is thinking or

feeling, and to respond to their thoughts and feelings with an appropriate emotion”

(p. 12), which suggests two stages of empathy: recognition and response. From a

conceptual perspective, empathy can be regarded a very broad term which is related

to a plethora of more finely defined terms used for a more comprehensive

categorization (e.g., mimicry, emotional contagion, sympathy, and compassion)

(Singer & Lamm, 2009).

Singer and Lamm (2009) stress the importance of the self-other distinction, in

other words, our ability to distinguish between whether or not the source of an

emotional response lies within ourselves or was triggered by the other. They further

distinguish between, on the one hand, empathy – and sympathy, empathic concern,

and compassion, on the other. Empathy allows one to “feel with” someone, whereas

the latter terms allow one to feel “for someone”. The practical difference between

these two is: feeling sadness for someone who is sad, rather than merely feeling pity,

or concern, for someone who is sad. Pity is not the appropriate empathic response, but

it may be a compassionate response. Also, if an observer notices that someone is

jealous of him, feeling jealousy towards that person is not an appropriate response,

feeling sorry for that person would be more appropriate (Singer & Lamm, 2009; for

similar arguments, cf. de Vignemont & Singer, 2006).

Singer and Lamm (2009) argue the self-other distinction is crucial, and that

many researchers have used these terms synonymously, thus creating both confusion,

and widely used psychometric measuring tools, which rely solely on self-report.

Ultimately, “empathy is conceived to be a first necessary step in a chain that begins

with affect sharing, followed by understanding the other person’s feelings, which then


motivates other-related concern and finally engagement in helping behavior” (Singer

& Lamm, 2009, p. 84). For a comprehensive list of distinctions currently used by

researchers in this field, see Batson (2009).

The terms empathy and sympathy have been used in various different ways in

scientific literature (cf. Dolan & Fullam, 2007), however, sympathy is not a concept

that this thesis will take into consideration. This thesis will treat empathy in

accordance with Blair’s (2007a) tripartite division into motor empathy, cognitive

empathy – also referred to as theory of mind (ToM; Premack & Woodruff, 1978), or

mentalizing (Frith, Morton, & Leslie, 1991) – and affective, or emotional empathy.

Motor empathy refers to where the individual mirrors the motor responses of the

observed actor; cognitive empathy refers to where the individual represents the

internal mental state of the other; and affective empathy refers to an individual’s

congruent emotional response to another individual’s emotional state (Blair, 2007a).

Cognitive and Affective Empathy

The scientific consensus is that the severe empathic dysfunction evident in

psychopaths is mainly due to lack of emotional (or what is also referred to as affective)

empathy, but with intact cognitive empathy (Blair, 2005, 2007a; Cox et al., 2012).

However, this is a complicated subject, partly due to the lack of scientific consensus

regarding the composition of the empathy construct (Blair, 2005; Mullins-Nelson,

Salekin, & Leistico, 2006). Happé and Frith (1996) found similarities between autistic

children and children with conduct disorder (CD) – which is a diagnosis similar to that

of adult ASPD – specifically, that both groups have difficulties with cognitive empathy

in comparison to control groups. Partly based on this finding, Söderström, Blennow,

Sjödin, and Forsman (2003) argue that psychopathic individuals are empathically

deficient in more aspects than the affective department. Blair (2007a) disagrees with

this conclusion. He argues that both ASPD and CD are flawed diagnoses, being that

the diagnostic rate of CD can reach more than 16% of boys in the general population

(DSM-IV; American Psychiatric Association, 1994). The same imprecision is found in

ASPD, which can reach a diagnostic rate of 50-80% in adult forensic institutions


(Ogloff, 2006). Blair (2007a) caveats that because of these imprecisions, researchers

need to be careful not to treat the constructs as more similar than they actually are.

Dolan and Fullam (2004) proposed that the deficits in cognitive empathy in

individuals with ASPD are subtle. They performed a variety of ToM tasks and found

significant differences during the so called faux pas task. The faux pas task is

described in the following way:

A faux pas occurs when someone says something that they should not have

said without realizing that they should not have said it. An understanding

of faux pas requires a person to represent the mental state of both the

speaker and hearer of the faux pas, i.e. it requires an understanding that

the speaker does not realize they should not have said it, and that the

person on the receiving end of the faux pas will feel hurt or insulted (Dolan

& Fullam, 2004, p. 1096).

The subjects were asked a series of questions pertaining to the mental state of

both the speaker and listener. An additional control question was asked in order to

make sure that the subjects were able to follow and understand the elements of the

story, and further, their ability to recognize how the people in the story might have

felt. Results showed significant differences between criminals (both psychopathic and

non-psychopathic) and controls, regarding the assessment of the mental state of both

the speaker and listener. There were no significant group differences in the control

question, indicating that the subjects were able to follow the story in a similar fashion.

Regarding the empathy related question, both psychopathic and non-psychopathic

criminals were impaired in comparison to controls. In conclusion, Dolan and Fullam

(2004) argue that the deficits found in psychopaths seem to relate to a general lack of

concern regarding the impact of their actions, rather than an inability to understand

that their actions impact others.

Very few studies have been conducted regarding empathy in subclinical

psychopaths – only one, according to Mullins-Nelson et al. (2006) – but at least one

more study has been conducted since then (viz. Gao & Raine, 2010). Mullins-Nelson


et al. (2006) studied psychopathy in a college population, and its relation to both

cognitive and affective empathy. The measuring instrument used was the Psychopathic

Personality Inventory–Short Form (PPI–SF; Lilienfeld & Andrews, 1996), an abridged

version of the PPI (Lilienfeld & Andrews, 1996), both of which are self-report

instruments. Both components of empathy were measured with the Interpersonal

Reactivity Index (IRI; Davis, 1983), which is also a self-measurement instrument. The

participant sample was composed of 44 males (25%) and 130 females (75%), which is

important to note due to the significant gender differences regarding subjective

reporting in both cognitive and emotional empathy (Baron-Cohen & Wheelwright,

2004; Schulte-Rüther, Markowitsch, Fink, & Piefke, 2007). As expected, the results

showed that the high scorers on the PPI–SF did not differ in their perspective-taking

ability (cognitive empathy), but they were also less likely to demonstrate affective

empathy, thus reinforcing the picture of the psychopath as someone who simply does

not care about negative consequences (Mullins-Nelson et al., 2006).

The original version of the PPI was based on eight subscales which, in the

PPI–SF, are condensed into two factors: stress immunity, social potency, fearlessness,

and coldheartedness (PPI–SF–I); and impulsive nonconformity, blame externalization,

Machiavellian egocentricity, and carefree non-planfulness (PPI–SF–II). Upon studying

the specific factors, the researchers found that high scorers on the psychopathy

measurement that also scored highly on the PPI–SF–II evidenced deficits in almost all

aspects of emotional functioning, including cognitive empathy. In accordance with

these findings, the researchers argue that the successful psychopath may be one that

scores high on the first factor but not on the second factor (Mullins-Nelson et al.,

2006).

Lilienfeld and Fowler (2006) have discussed several drawbacks with the PPI

instrument. Self-report instruments are always problematic, but especially when

dealing with psychopaths, who in their very nature are manipulative, and dishonest.

Psychopaths tend to lie either for some personal gain, or simply because they find it

entertaining, a phenomenon Ekman (1985) referred to as duping delight. A second


problem is the lack of insight any person may have into one’s personality, but with

psychopaths, who tend to have an unrealistic world view (e.g., lack of realistic long

term goals), the problem becomes even more significant. Third, asking individuals

who have an inherent lack of emotions (or at least an inability to utilize their emotions

in any meaningful way) what they feel is in and of itself problematic. For a lengthier

discussion of these matters, see Lilienfeld and Fowler (2006).

Motor Empathy

In relatively recent years, a further constructional division of empathy, known as

motor empathy, has been made (Carr, Iacoboni, Dubeau, Mazziotta, & Lenzi, 2003).

This account has its basis in the discovery of mirror neurons (Di Pellegrino, Fadiga,

Fogassi, Gallese, & Rizzolatti, 1992; Rizzolatti, Fadiga, Gallese, & Fogassi, 1996),

which are neurons that show activity during the execution of an action, and also

during the observation of the same or a similar action (Iacoboni, 2009). Evidence

suggests that motor empathy is when we understand what others feel, as relayed by a

mechanism of action representation. Our empathic emotions are therefore, at least

partially, moderated by the emotions associated with a specific movement (Carr et al.,

2003). The motor mirror neuron system is believed to be composed of regions in the

posterior inferior frontal gyrus (IFG) the ventral premotor cortex, and the rostral

inferior parietal lobule (IPL) (Shanton & Goldman, 2010). Whether or not

psychopathic individuals have deficient motor empathy is under debate. However,

Blair (2005) argues that this is unlikely, and that their empathic deficiencies are

limited to marked facial expressions and selective emotional empathy.

Avenanti, Bueti, Galati, and Aglioti (2005) studied what happens with motor

responses when a normal person (as opposed to a psychopath) observes a model hand

being pricked by a needle. They used transcranial magnetic stimulation (TMS)-induced

motor evoked potentials (MEP) to measure motor cortex excitability and the results

showed a reduction of MEP amplitude that was specific to the muscle that subjects

observed being pricked. The increase of reduction correlated with the observer’s

subjective empathic rating of the sensory, but not affective, qualities of the pain


ascribed to the model. Fecteau, Pascual-Leone, and Théoret (2008) used the PPI

(Lilienfeld & Andrews, 1996) in conjunction with the TMS-MEP methodology, in an

endeavor to find out whether or not psychopathic individuals would show the same

reduction. Their results showed that high scores on a PPI subscale called

coldheartedness correlated significantly with reduction in MEP amplitude, which

suggests that individuals with specific psychopathic characteristics (those related to

the coldheartedness subscale) are, at a sensorimotor level, more responsive than

individuals with a lower coldheartedness score. Lilienfeld and Andrews (1996) define

coldheartedness as “a propensity toward callousness, guiltlessness, and

unsentimentality” (p. 495). The coldheartedness factor correlates significantly to

Factor 1 of the PCL-R (Hare, 1991), but not to Factor 2 (Poythress, Edens, & Lilienfeld,

1998). The finding of Fecteau et al. (2008) gives credence to Blair’s (2005) conjecture

that psychopaths have intact motor empathy and that their lack of guilt or remorse

must be attributed to some other cognitive faculty.

Empathizing–Systemizing Theory

Simon Baron-Cohen has developed a theory known as the empathizing–

systemizing theory (E–S Theory; Baron-Cohen, Knickmeyer, & Belmonte, 2005). The

systemizing component of the theory incorporates the notion that the brain looks for

patterns in order to figure out how the world is connected, and how to predict the

future. The empathizing component is simply one’s ability and interest in empathizing

with someone else; both aspects conform to normal distribution. The theory states

that psychopathy is the polar opposite of autism. The hypothesis being that autistic

individuals have difficulties in understanding the emotional states of others, but if and

when they do understand them, they have the capacity to empathize. The psychopath

on the other hand, has the ability to understand that the observer feels, but not how or

what it feels (Baron-Cohen, 2012).

In 2006, Auyeung et al. examined fetal testosterone levels and its relation to

systemizing ability. The study found a significant difference in systemizing quotient

(SQ) between boys (mean = 27.79 ± 7.64) and girls (mean = 22.59 ± 7.53), thus


confirming the hypothesis that boys systemize to a larger extent than girls (Auyeung

et al., 2006), which connects to the fact that male fetuses are exposed to higher levels

of testosterone than are female fetuses (Knickmeyer & Baron-Cohen, 2006). Another

study found a significant negative correlation between fetal testosterone and measures

on an empathy task. The authors concede that levels of empathy are likely to be

influenced by post-natal experience that may override the pre-natal biological

environment (Chapman et al., 2006)

Testosterone has been proposed as an important part of psychopathy, due to its

relation to aggression – which is defined as behaviors that are intended to inflict harm

(Nelson & Trainor, 2007). However, very few studies have been published on the

subject to this date. Glenn, Raine, Schug, Gao, and Granger (2011) investigated the

ratio between cortisol and testosterone, because it had been suggested that the

cortisol-testosterone-ratio was associated with psychopathy (Terburg, Morgan, &

van Honk, 2009). The researchers were unable to find significant results when

manipulating the participants with stress, but they did observe a significant

relationship between baseline cortisol, and testosterone, which accounted for about

5% of the variance in psychopathic traits.

Söderström et al. (2001, 2003) conducted two consecutive studies

that showed a correlation between psychopathy and an increased ratio between

serotonin (5–HIAA), and dopamine (HVA) metabolites. This may have an effect on the

disinhibition of aggressive impulses that is typical of psychopaths. Thus, combining

dopamine and serotonin regulation may improve impulse control in psychopaths.

The neurotransmitter serotonin (5–HT) has been proposed to – in combination with a

high testosterone-cortisol ratio – facilitate between instrumental (i.e., associated with

premeditation, and not merely violence as a consequence of an affective reaction),

and impulsive aggression. Specifically, low cortisol, high testosterone and low levels

of 5–HT is believed to predispose impulsive aggression (Montoya, Terburg, Bos, &

van Honk, 2012; Terburg et al., 2009; van Honk, Harmon-Jones, Morgan, & Schutter,

2010). For a review of the neuroanatomy of aggression, see Nelson and Trainor (2007).


Furthermore, studies have shown that increased serotonin in the hypothalamus

may increase the production of cortisol (Glenn & Raine, 2008); thus, dysregulation of

serotonin may be connected to the low levels of cortisol observed in psychopaths. It is

also a possibility that serotonin interacts with testosterone levels and increase the

probability of aggression. One such study showed that high testosterone and low

serotonin may correlate to both intensity, and rates of aggression (Higley et al., 1996).

Glenn and Raine (2008) caution readers that the neuroendocrinology of psychopathy

is in its early stages: thorough understanding of the neurobiology of psychopathy

requires not only knowledge of brain region involvement, genetics, neurotransmitters,

and hormones, but rather, an assembly of all of these aspects. An important criticism

has been raised by Ellis, Beaver, and Wright (2009). In a discussion regarding

testosterone, they comment that most studies either use blood or saliva to measure

testosterone, neither of which are ideal measurements when it comes to behavior. The

brain causes behavior, blood and saliva do not. Therefore, they argue that it is

important to measure the levels of testosterone (and possibly many other hormones)

in the brain, which is most effectively carried out by performing a lumbar puncture,

which is a painful and invasive procedure that researchers often do not use.

At least 13 brain regions have been suggested to be part of the empathy network

(Baron-Cohen, 2012), which sheds some light on how complex the empathy construct

is. Empathy has been studied in a wide variety of ways, across several different

domains. Neuroimaging studies have been performed for a multitude of different

aspects of empathy, such as pain (Coll, Budell, Rainville, Decety, & Jackson, 2012;

Singer et al., 2004), disgust (Jabbi, Swart, & Keysers, 2007), touch (Keysers et al.,

2004), anxiety (Morelli, Rameson, & Lieberman, 2012), happiness, and anger

(Dimberg & Thunberg, 2012). In addition, empathy induction procedures are

traditionally either simple observation (Keysers et al., 2004), imagination (Jackson,

Brunet, Meltzoff, & Decety, 2006), or evaluation (Jackson, Meltzoff, & Decety, 2005).

The high variation in these studies do not make it clear, which, if any, underlying

neural regions that are consistently active in all, or most, scenarios. This was


subsequently investigated by Fan, Duncan, de Greck, and Northoff (2011), who

identified several clusters relevant for different empathy paradigms: the anterior

midcingulate cortex, dorsal anterior cingulate cortex (ACC), supplementary motor

area, and bilateral anterior insula (AI). The researchers confirmed their hypothesis

that these four areas are the core networks that lays the foundation for empathy.

However, the affective–perceptual and cognitive–evaluative forms of empathy are

believed to have different neural bases, but with extensive interconnections between

the two areas, which suggests a detailed division of specific functions. The affective

network has been suggested to be comprised of the right AI, thalamus, and

periaqueductal gray (PAG) (Kober et al., 2008). The cognitive-evaluative form of

empathy seems to be carried out by the left AI alone, but more thorough research is

yet to be carried out (Fan et al., 2011).

Additionally, based on the findings of the mirror neuron system (Di Pellegrino

et al., 1992; Rizzolatti et al., 1996), some researchers have proposed simulation as an

intimate component of empathy (Gallese, 2001, 2003; Schulte-Rüther et al., 2007).

Fan et al. (2011) did not find any evidence to suggest that the areas believed to be

involved in simulation (e.g., the left IFG and IPL) were consistently active during

empathizing. The researchers make caution that this discovery is by no means final,

and that simulation may be a core part of empathy, though not in terms of consistent

neural activity.

Shamay-Tsoory (2011) has hypothesized that the cognitive and affective

components of empathy are dissociable systems. Evidence is support of this claim

comes from ethological, psychiatric, and developmental studies. There is also evidence

that suggests that the neurotransmitter oxytocin plays a large role in emotional

empathy, but not in cognitive empathy (Hurlemann et al., 2010). Shamay-Tsoory

(2011) further suggests that the IFG and IPL are involved in simulation, which along

with the insular cortex and ACC makes up the emotional empathy network. The

cognitive network is believed to be comprised of the ventromedial prefrontal cortex

(VMPFC), dorsomedial prefrontal cortex (DMPFC), temporoparietal junction, and


medial temporal lobe (MTL). This network is believed to be involved with both

cognitive and affective mentalizing processes.

Thoma, Friedmann, and Suchan (2013) has commented that studies on

psychopathy has provided some support for the hypothesis that they are cognitively

impaired and that little has been done to investigate emotional empathy. Further, they

urge researchers to differentiate between subclinical and clinical psychopaths, because

of their importance in relation to cognitive and emotional empathy.

The Neurophysiological Basis of Psychopathy

Neuroscientists have looked for brain abnormalities in psychopaths since the

time of Phineas Gage. In 1848, Gage was severely injured by an iron rod which passed

through his skull, penetrating his prefrontal cortex (PFC) — mainly the orbitofrontal

cortex (OFC) — leaving Gage with profound personality changes (O’Driscoll & Leach,

1998). Gage, as well as other patients with similar damage, has been diagnosed as

having acquired sociopathy or pseudopsychopathy, which is categorized by impulsive

and antisocial behavior. Blair (2003) has commented that pseudopsychopaths do not

exhibit the instrumental violence typical of psychopaths, which is consistent with the

behavior of Gage, who became aggressive and exhibited reactive (impulsive) violence

Raine and Yang (2006b). Further evidence for this theory has been provided by

Broomhall’s (2005) finding that pseudopsychopaths tend to score highly only on

PCL-R factor 2, whereas clinical psychopaths score highly on both factors.

Structural Deficits and Abnormalities in Psychopaths

Amygdala. The amygdala has played a major role in hypotheses regarding the

psychopathy construct (Baron-Cohen, 2012; Blair, 2003, 2008; Kiehl, 2006; Raine &

Yang, 2006a; Yang, Glenn, & Raine, 2008). The amygdala is known to play a major

role in fear condition and emotion recognition (Adolphs, Tranel, Damasio, & Damasio,

1994; Adolphs & Tranel, 2003), as well as both increasing and decreasing aggressive

behavior (Blair, 2004). The decrease in aggression was seen in a patient after a

bilateral amygdalectomy (Ramamurthi, 1988), and increases in aggression have been


seen in patients with temporal lobe epilepsy (Van Elst, Woermann, Lemieux,

Thompson, & Trimble, 2000). Deficits in the amygdala have further been linked to

both social behavior and moral emotion (Adolphs, Tranel, & Damasio, 1998; Blair,

2007b). Specifically, studies have shown that psychopaths demonstrate a lower level

of amygdala activation when looking at fearful faces (Dolan & Fullam, 2009), or

moral violations (Harenski, Harenski, Shane, & Kiehl, 2010), in comparison to

controls. In terms of anatomical structure, Ermer, and colleagues (2012) conducted a

large-scale study involving 296 participants. The researchers found decreased regional

gray matter in several paralimbic and limbic areas, including bilateral

parahippocampal, amygdala, and hippocampal regions, bilateral temporal pole,

posterior cingulate cortex, and OFC. These findings were still relevant after controlling

for substance abuse, brain size, and age. Furthermore, they argue that these results

suggest that psychopathy may have its basis in a broader system of neural regions than

expected (Ermer, Cope, Nyalakanti, Calhoun, & Kiehl, 2012).

Thus, the amygdala may be intimately related to many aspects of psychopathic

behavior. Because both clinical and subclinical psychopaths have deficiencies in

affective empathy, it may be the case that damage to the amygdala will be

distinguishable only in comparison to controls, but not to subclinical psychopaths.

This question was investigated by Yang, Raine, Colletti, Toga, and Narr (2010). They

hypothesized that clinical psychopaths, but not subclinical psychopaths, would show

significant volume reductions in the OFC, dorsolateral prefrontal cortex (DLPFC), and

the amygdala, compared to controls. The group confirmed their hypothesis in finding

structural deficits in both prefrontal areas and the amygdala pertaining to clinical

psychopaths, but not subclinical psychopaths. Furthermore, clinical psychopaths

showed a 26% volume reduction in the left amygdala, and 20% reduction in the right

amygdala, compared to controls. In the subclinical psychopaths, the observed volume

reduction was smaller, notably 9.3% in the left, and 12.7% in the right amygdala.

Follow up analysis revealed that socioeconomic status or substance abuse was unlikely

to have an effect on the results.


There is a related question regarding whether there are different brain deficits

associated with different types of psychopathic behavior, specifically, whether, and

how, variations in neurological disposition relate to instrumental versus affective

violence. Psychopathic offenders display a higher rate of both community, and

institutional violence than forensic patients, and the more general offender (Hart &

Hare, 1997; Hill, Rogers, & Bickford, 1996). A study by Woodworth and Porter (2002)

revealed that psychopaths show a much higher degree of instrumental violence than

nonpsychopaths. Their study showed that nearly all (93.3%) of the homicides

committed by psychopaths was primarily instrumental, compared to 48.4% in

nonpsychopaths. It should be noted that definitions and evaluations of instrumental

and affective violence are problematic, in the sense that they do not conform to a

scientific consensus.

Prefrontal cortex. Yang et al. (2005) found a negative correlation between

higher total PCL-R score and low gray matter volume in the PFC. Clinical psychopaths

had 22.3% reduction in prefrontal gray matter volume in comparison to controls.

Subclinical psychopaths, on the other hand, showed very little reduction

(non-significant) in prefrontal gray matter, which is evidence of an important

difference between the two. Increase in PCL-R score has also been found to be related

to reduction of cortical thickness in both temporal, and prefrontal gray matter (Yang,

Raine, Colletti, Toga, & Narr, 2009). A few studies found similar results in

psychopaths, and in alcoholics with antisocial personality disorder (Dolan, Deakin,

Roberts, & Anderson, 2002; Laakso et al., 2002). However, after controlling for

education and alcoholism, these significant differences in brain volume disappeared,

which has led to questions as to whether only clinical psychopaths are afflicted by

such structural impairments (Yang et al., 2009).

The OFC is the most common prefrontal region implicated neuroimaging

investigations of psychopathy (Anderson & Kiehl, 2012). Yang et al. (2010) published

the first study that found significant structural differences between clinical and

subclinical psychopaths in relation to the medial frontal cortex (MFC), and OFC. They


defined subclinical (they refer to it as successful) psychopaths as individuals with high

PCL-R scores that managed to escape detection for their crimes. A PCL-R cutoff score

of 23 and above was used. It should be noted that both groups reported that they had

committed the same number of crimes on average, 9.88 for the clinical group, and

9.37 for the subclinical group. In this case, the clinical psychopaths had higher

socioeconomic status than the subclinical group, although the difference was not

statistically significant (p = 0.06). The results showed structural deficits in MFC, OFC,

and amygdala in clinical psychopaths, but not in subclinical psychopaths. Interestingly,

the subclinical psychopaths had higher gray matter volume in the left middle frontal

cortex and superior frontal cortex than normal controls (Yang et al., 2010).

Though not directly related to psychopathy, Raine et al. (1998) observed that

impulsive murderers have lower prefrontal activity than predatory murderers.

Common to both groups were increased subcortical activity (midbrain, amygdala,

hippocampus, and thalamus) in comparison to controls. This supports the intuitive

hypothesis that the deficient prefrontal functioning prohibits the impulsive murderer

from regulating, and controlling aggressive impulses (Raine & Yang, 2006b).

Temporal lobe. Dolan et al. (2002) revealed a 20% volume reduction of the

temporal cortex in incarcerated personality-disordered offenders. These offenders

corresponded more closely to the ASPD criteria, which makes the finding difficult to

generalize, especially against the population of subclinical psychopaths. As noted

above, Yang et al. (2009) reported reductions in gray matter thickness in the anterior

and MTL, and also in the superior temporal regions and the insula. Müller et al.

(2008) found significant gray matter reductions in frontal and temporal brain regions

in psychopaths compared with controls. A specifically high volume loss was found in

the right superior temporal gyrus. In contrast to the prefrontal, and the left temporal

finding, right temporal volume loss was not because of other correlates, such as

education, alcohol, or drug consumption (Müller et al., 2008).

Hippocampus. Raine et al. (2004) reported an exaggerated anterior

hippocampal volume asymmetry (right > left) in clinical psychopaths, relative to both


control, and subclinical psychopaths. Neither environmental factors nor diagnostic

confounds could explain the phenomenon, which led the researchers to propose that

the asymmetry is probably a developmental problem.

Corpus callosum. Raine et al. (2003) investigated the potential differences in

the corpus callosum between 15 male subjects with high psychopathy scores, and

ASPD, as compared to controls. The ASPD subjects showed 22.6% increase in

estimated callosal white matter volume, 6.9% increase in callosal length, 15.3%

reduction in callosal thickness, and increased functional interhemispheric connectivity.

Larger callosal volumes were associated with affective and interpersonal deficits, low

autonomic stress reactivity, and low spatial ability.

Neuroimaging and Empathy

According to Decety, Skelly, and Kiehl (2013), the neural processes linked to

empathy have only been investigated with functional magnetic resonance imaging

(fMRI) once, in psychopaths. The group of researchers used a total of 80 men

incarcerated in a medium security correctional facility. The participants underwent a

full PCL-R investigation, including file reviews, and interviews. Those scoring 30 or

more on the PCL-R were assigned to a high-psychopathy group (n=27). Scores of

21-29 (n=28) were assigned to a medium-psychopathy group. The third group was

low-psychopathy scorers (n=25), with a score of 20 or less. Furthermore, second-level

analyses were conducted in order to compare PCL-R extremes. Participants with 30 or

more were selected for the psychopathy group, and 20 or less for the control group.

The subsequent testing involved two tasks for examining the neural processes linked

to empathy when observing others being harmed, or making pained facial expressions.

Participants in the psychopathy group showed less activation in the VMPFC, lateral

OFC, and PAG, in comparison to controls. Interestingly, the lateral, and medial parts of

the OFC are extensively interconnected with the amygdala, and hypothalamus, which

are involved in the mediation of emotional and affective behavior (Blair, 2003;

Decety, 2010a; Weber, Habel, Amunts, & Schneider, 2008). The psychopaths also

exhibited greater activation in the insula, which positively correlated with scores on


both PCL-R factors. The participants also showed greater activation in the anterior

insula (AI), dorsal striatum, dorsomedial prefrontal cortex, and posterior superior

temporal sulcus, where the latter three are involved in the cognitive aspect of

empathy, or ToM (Abu-Akel & Shamay-Tsoory, 2011; Carrington & Bailey, 2009;

Van Overwalle & Baetens, 2009). Decety et al. (2013) find the high activity in the AIC

surprising, due to it being the most consistently active brain region across all studies

concerning pain related empathy (Decety, 2010b; Lamm, Decety, & Singer, 2011).

Discussion

In the introduction, two hypotheses were stated which have by now been

discussed both theoretically and empirically. The first hypothesis regards the current

conceptualization of subclinical psychopathy, specifically, that the conceptualization of

subclinical psychopathy is flawed, because the criterion for being a subclinical

psychopath is arbitrary. The second hypothesis is that there is some difference

between clinical and subclinical psychopaths, and by this, I do not simply mean a

difference of location (institutionalized or not), but rather, that there is a substantial

difference in behavior.

The empirical evidence supporting the second thesis is, I think, convincing. The

structural deficits found in clinical but not subclinical psychopaths are a solid

foundation in support of the claim that there must be a significant difference. In a few

of the studies reviewed, the subclinical psychopath has been found to have more gray

matter than both clinical psychopaths and non-psychopathic controls. This suggests

that the subclinical psychopath may be anatomically different in a way that allows him

to, for one reason or another, behave in a significantly less antisocial manner.

However, the behavior of an individual is not possible to simply reduce to how much

white or gray matter there is in a given brain area. Due to factors such as neural

plasticity, the brain may utilize alternative pathways and thus the same function (i.e.,

behavior) may be retained. Ultimately, concluding that structural deficits of up to 26%

in the amygdala in clinical psychopaths (Yang et al., 2010) do not mean anything


whatsoever, is quite a stretch. Furthermore, at least one study has shown that

psychopaths may be different on a sensorimotor level, specifically in regards to motor

empathy (Fecteau et al., 2008). This study relied on self-measurement instruments in

order to assess psychopathy, which renders the study a bit more problematic. In any

case, studies such as these are important because they prod the important questions

and return valuable information; which brings me to the second hypothesis.

The first hypothesis is the chief concern of this thesis, and relates to the issue of

how subclinical psychopathy is currently discussed. The conceptualization of

subclinical psychopathy has, to my knowledge, not been established in any finer detail

than by how it has been presented in this thesis. Accordingly, subclinical psychopathy

refers to individuals that refrain from criminal activity for one reason or another. The

value of a distinction comes from what the distinction is supposed to be used for. Gao

and Raine (2010) proposed three reasons for studying subclinical psychopathy. The

first reason is to determine, with a greater degree of certainty, what the prevalence

rate of psychopathy is. Second, subclinical psychopaths may not be exactly like clinical

psychopaths, and hence, studying subclinical psychopaths may lead to etiological

insights. Third, understanding how subclinical psychopaths operate may help with

rehabilitation of all psychopaths. These three reasons are all good reasons for studying

subclinical psychopathy. The problem is that the current conceptualization is

ambiguous and depends on poorly chosen criteria.

To illuminate what I am referring to, one particular comment by Gao and Raine

(2010) can be analyzed. They proposed that serial killers who evade law enforcement

for long periods of time could constitute a form of semi-successful psychopathy. In my

opinion, this terminology speaks volumes about the intrinsic flaw in the

clinical-subclinical distinction, because subclinical psychopaths are supposedly not as

intensely antisocial as clinical psychopaths. It is difficult to imagine a group of people

that are more severely antisocial than serial killers, and thus, even amongst

researchers, there exists a conceptual inconsistency that needs resolution.

There is a long standing tradition amongst psychopathy researchers to regard the


entire construct as a subset of ASPD, as seen in Herpertz and Saß (2000). Coid and

Ullrich (2010) even goes so far as to suggest that ASPD and psychopathy belong on

the same spectrum. They argue that the cut-off point used when diagnosing

psychopaths with the PCL-R is arbitrary and that this has created a gap between the

constructs which is uncalled for. It should be noted that this is a controversial position

that does not conform to consensus. Other researchers have argued for the exact

opposite position, namely, that ASPD and psychopathy are two very different

constructs (Hare, 1996; Hare & Neumann, 2006; Perez, 2012). However, subclinical

psychopathy is very rarely mentioned in conceptual debates and it is not obvious that

subclinical psychopathy is simply a subset of psychopathy. The consequence of the

current conceptualization is that subclinical psychopaths are forced into the same

category as both clinical psychopaths, and in some conceptualizations, in the ASPD

category. This categorization must result in that subclinical psychopaths are

categorized as severely antisocial, which they, by definition, should not be.

The issue is that the behavior of subclinical psychopaths must be put into

question. Is there such a thing as a subclinical psychopath with a pervasive pattern of

antisocial behavior? The only criterion for determining whether or not an individual is

a clinical or subclinical psychopath depends on that individual’s location (i.e. mental

institution or prison), and this is problematic. As long as a psychopathic individual

behaves in a way that is tolerated (in the sense that he is able to get away with

whatever it is he is doing) within a given context and circumstance – the result must

be that the individual is classified as a subclinical psychopath. This is not a problem at

all if the point of the clinical-subclinical distinction is to determine where an

individual is located, but this hardly requires extra terminology. The conceptual

problem arises when one reflects about the reasons for studying subclinical

psychopaths. If these two groups are behaviorally different, which it stands to reason

that they are, then it may be possible to base the criteria on behavior.

In the subsequent discussion two things will be discussed: the problems of

psychopathy and empathy research, and a few areas where more research is needed.


The empathy construct is an incredibly complex one, believed to involve at least 13

brain regions (Baron-Cohen, 2012). Apart from the terminology, which definitely

plays a role in the ambiguous nature of empathy, measuring empathy is very

problematic. Most research relies on self-measurement instruments, the problems of

which have been discussed previously. In relation to psychopathy, the main problem

with empathy is arguably that surprisingly few studies have been conducted,

especially concerning emotional empathy (Thoma et al., 2013). This is very peculiar,

because many theorize that lack of empathy is the key component of psychopathy.

Thus, breakthroughs in the field could lead to improvements in terms of rehabilitation.

Treatments need to distinguish between different empathic deficits, because antisocial

behavior has been linked to deficits in cognitive empathy to a larger extent than

affective empathy (Jolliffe & Farrington, 2004), and hence, interventions in antisocial

behaviors may need to focus on the former type.

The recently published fMRI-study by Decety et al. (2013) is an important one,

because it is a starting point when it comes to studying empathy with imaging

techniques in psychopaths. There remain many elusive facts regarding empathy that

are crucial in order to understand both psychopathy and empathy. Without a thorough

understanding of the relation between cognitive and affective empathy, drawing

conclusions regarding psychopathy will be problematic.

In order to improve insight into subclinical psychopathy, it may be beneficial to

control for PCL-R scores (on all four PCL-R facets) between groups. Other possible

confounding factors include intelligence, personality traits, socioeconomic status,

education, parenting (or other protective environmental factors), alcohol, and drug

abuse. Most of these factors have been studied regarding clinical psychopathy, but

remain unexplored concerning subclinical psychopathy. Furthermore, discussing all of

these topics is beyond the scope of this thesis, but a few words will be written about

gender, intelligence and personality.

Most psychopathy research is conducted with male participants, but studies on

female psychopaths have shown quite significant behavioral differences. These


differences may play a role in the difficulty of delineating the psychopathy construct,

as well as making it difficult to establish prevalence rates. Female psychopaths are

interesting in relation to subclinical psychopaths, because their behavior seems to be

less severely antisocial (in terms of violence and aggression); but they are also

interesting in relation to empathy and emotions in general. It may be the case that

female psychopaths are less callous than male psychopaths and thus, it is a possibility

that empathy is a moderating factor.

Intelligence and personality are interesting aspects of psychopathy that could

yield significant etiological insight. However, very few studies have been conducted

regarding both topics in relation to clinical psychopathy, and there is no study known

to the author regarding subclinical psychopaths in particular. Costa and MacCrae’s

(1992) five factor model of personality has been used to study psychopaths, but the

results of such studies are not of relevance to this topic, because no contrasting results

in subclinical psychopaths have been studied. Neuroscience has not yet reached a

stage at which it is possible to meaningfully infer behavior based on brain scans.

Hence, a social psychological perspective may be an efficient way of establishing

specific behavioral differences between the two psychopathy groups, which in turn

may lead to the possibility of clarifying the concepts involved.

Three frameworks for assessing the status of subclinical psychopathy have been

presented. Proponents of the first framework argue that the difference between

clinical and subclinical psychopaths is one of degree, not of type. Advocates of the

second suggest that both types share etiology and pathology, which means that the

essential difference is a matter of socialization. Good parenting, special talent, high

intelligence etc. is said to hinder the individual from fully developing into a clinical

psychopath. The third framework posits that there are two distinct etiologies, which

allow for the possibility of scoring high on one, and low on the other. This approach

converges well with the two factors of the PCL-R.

The second framework can be interpreted in a variety of ways, depending on

how strong of a claim one infers. The very strong claim would be to say that a good


upbringing will inevitably result in a well-functioning, pro-social individual. There is

quite a lot of anecdotal evidence to suggest that while a bad upbringing can have its

negative consequences, many also overcome such diversities. The same can be said

about a good upbringing, which in some cases ultimately results in antisocial behavior.

The weaker claim would be to say that the influence of socialization is significant, but

is not, in itself, enough to moderate the behavior of a significant neuroanatomical

deficit. Furthermore, these frameworks are not mutually exclusive. At the moment it is

very difficult to assess the epistemic status of the three frameworks, due to a lack of

research. The little evidence that do exist can be used in support of all three.

The frameworks spark the debate of difference as degree versus type. A

significant contribution to this debate can be foreseen in substantial advancements in

neuroscience, in terms of finding a double dissociation (e.g., Broca’s area and

Wernicke’s area). If one can demonstrate that damage to brain structure P impairs

affective empathy, but does not cause antisocial behavior, and that damage to brain

structure Q causes antisocial behavior, but spares affective empathy, one could infer

that the two areas are dissociable. With such evidence, the inference for a difference

in type would be very strong.

Studies pertaining to the neuroendocrinology of psychopathy may also prove

significant in the future. The field is currently in its infancy, but with continued

research and technical advancement, one can be hopeful about seeing significant

group differences in hormones and neurotransmitters. This includes Baron-Cohen’s

research regarding empathy and testosterone, which may one day prove to be

important aspects of psychopathy.

In conclusion: it has been argued that the conceptualization of subclinical

psychopathy is flawed and ultimately, my suggestion is that a better definition of

subclinical psychopathy would rely on both the available and the forthcoming

empirical data. Being that lack of empathy is a key aspect in both clinical and

subclinical psychopathy it needs to be studied extensively. Both the aspects of empathy

are relevant in order to understand psychopathic behavior, in both clinical and


subclinical psychopaths. With technical advancement and continued research, one can

be hopeful that more significant research will be carried out; the implications of which

may not only help in resolving etiological debates, but help in the treatment of

psychopathy.


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