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Visual Perceptual Visual Perceptual AssessmentAssessment
OCT 1172OCT 1172
February 1, 2005February 1, 2005
Gianna KnibbsGianna Knibbs
Shannon Shannon McCreadyMcCready
Jeffrey MillsJeffrey Mills
Melissa Melissa PeressottiPeressotti
Presentation OutlinePresentation Outline Description of Perception & Description of Perception &
Approaches/Theories of PerceptionApproaches/Theories of Perception Motor-Free Visual Perceptual Motor-Free Visual Perceptual
Assessment (MVPT)Assessment (MVPT) General features and application to theoriesGeneral features and application to theories
Loewenstein Occupational Therapy Loewenstein Occupational Therapy Cognitive Assessment (LOTCA)Cognitive Assessment (LOTCA) General features and application to theoriesGeneral features and application to theories
Comparison chart of psychometrics Comparison chart of psychometrics (LOTCA, MVPT)(LOTCA, MVPT)
Two practical applicationsTwo practical applications
DefinitionsDefinitions
PerceptionPerception ““The dynamic process of receiving the The dynamic process of receiving the
environment through sensory impulses environment through sensory impulses and translating those impulses into and translating those impulses into meaning based on a previously meaning based on a previously developed understanding of that developed understanding of that environment” (Bouska et al., 1990)environment” (Bouska et al., 1990)
Definitions (2)Definitions (2) Visual PerceptionVisual Perception
““ability to identity, organize, interpret and ability to identity, organize, interpret and comprehend visual information received comprehend visual information received by a person through his or her eyes” by a person through his or her eyes”
(Hammill (Hammill et alet al., ., 1993)1993)
Approaches to Approaches to Understanding PerceptionUnderstanding Perception
Bottom-Up ProcessingBottom-Up Processing Primary perceptual processes convert Primary perceptual processes convert
sensation into perceptionsensation into perception Assessment and treatment approached by Assessment and treatment approached by
evaluating individual domains of functionevaluating individual domains of function Top-Down ProcessingTop-Down Processing
Our learned experiences narrow possible Our learned experiences narrow possible interpretations of the sensory stimuli in the interpretations of the sensory stimuli in the environmentenvironment
Assessment and treatment through Assessment and treatment through observation of a person engaging in functionobservation of a person engaging in function
Theories of PerceptionTheories of Perception
Luria’s Functional Systems Model Luria’s Functional Systems Model (1975)(1975) Model based on brain functioningModel based on brain functioning Interaction of various regions in the brain Interaction of various regions in the brain
is the cause of all human cognition and is the cause of all human cognition and functioningfunctioning
Grouped areas into 3 distinct Grouped areas into 3 distinct functional functional unitsunits
Each unit does NOT work in isolation of Each unit does NOT work in isolation of each othereach other
Theories of Perception Theories of Perception (2)(2)
Luria cont’dLuria cont’d First Functional UnitFirst Functional Unit::
Brainstem & reticular formationBrainstem & reticular formation Arousal and activationArousal and activation Involved in regulating tone, waking, and Involved in regulating tone, waking, and
mental statesmental states Stimulates us enough so we can do what we Stimulates us enough so we can do what we
have/need to dohave/need to do Also responsible for basic need states Also responsible for basic need states
(hunger, fight/flight responses)(hunger, fight/flight responses) Brain injury often results in deficits in the 1Brain injury often results in deficits in the 1stst
functional unitfunctional unit
Theories of Perception Theories of Perception (3)(3)
Luria cont’dLuria cont’d Second Functional UnitSecond Functional Unit::
**Where [visual] perception comes into **Where [visual] perception comes into play**play**
Posterior cortex; including the occipital, Posterior cortex; including the occipital, parietal, and temporal lobesparietal, and temporal lobes
Occipital lobe is key for visual perceptionOccipital lobe is key for visual perception Sensation and perceptionSensation and perception Each lobe is made up of 3 areas: primary, Each lobe is made up of 3 areas: primary,
secondary, tertiarysecondary, tertiary
Theories of Perception Theories of Perception (4)(4)
Luria cont’dLuria cont’d PrimaryPrimary::
Registers basic sensory information (ie. Auditory, Registers basic sensory information (ie. Auditory, visual, tactile)visual, tactile)
SecondarySecondary:: Sensations are integrated into actual perceptionsSensations are integrated into actual perceptions Ex. Sensations of light and structure becomes a Ex. Sensations of light and structure becomes a
perceived objectperceived object TertiaryTertiary::
Complex integration and elaboration of informationComplex integration and elaboration of information Ex. Reaching in your pocket and picking out a penny as Ex. Reaching in your pocket and picking out a penny as
opposed to a dimeopposed to a dime Ex. Interpreting verbal and nonverbal aspects of Ex. Interpreting verbal and nonverbal aspects of
communication – ie. Smile (happy)communication – ie. Smile (happy)
Theories of Perception Theories of Perception (5)(5)
Luria cont’dLuria cont’d Third Functional UnitThird Functional Unit::
Comprised of the frontal lobesComprised of the frontal lobes Maintains executive functioning and control Maintains executive functioning and control
over thought processes & actionsover thought processes & actions Main function is to inhibit unwanted Main function is to inhibit unwanted
information and behaviour. information and behaviour. It is involved in programming, regulating It is involved in programming, regulating
and verifying behaviourand verifying behaviour
Theories of Perception Theories of Perception (6)(6)
Piaget’s Theory of Piaget’s Theory of
Cognitive DevelopmentCognitive Development
Jean Piaget (Developmental psychology)Jean Piaget (Developmental psychology) ““How we come to know”How we come to know” ““Abstract symbolic reasoning”Abstract symbolic reasoning” Assimilation & AccommodationAssimilation & Accommodation
Motor-Free Visual Motor-Free Visual Perceptual Test (MVPT)Perceptual Test (MVPT)
Authors: R. Authors: R. Colarusso & D. Colarusso & D. Hammill Hammill
19721972
MVPT (2)MVPT (2)
PurposePurpose To measure visual perception free of To measure visual perception free of
motor involvementmotor involvement Used for screening, diagnostic, and Used for screening, diagnostic, and
for research purposes.for research purposes.
MVPT (3)MVPT (3)DomainsDomains Figure GroundFigure Ground::
Ability to distinguish an object from its backgroundAbility to distinguish an object from its background
Spatial RelationshipsSpatial Relationships:: Ability to switch the position of objects in relation Ability to switch the position of objects in relation
to oneself and/or other objectsto oneself and/or other objects Orienting one’s body in space & to perceive the Orienting one’s body in space & to perceive the
positions of objects in relation to oneself & to positions of objects in relation to oneself & to othersothers
DiscriminationDiscrimination:: Ability to distinguish dominant feature in different Ability to distinguish dominant feature in different
objectsobjects
MVPT (4)MVPT (4)
Domains cont’dDomains cont’d Visual ClosureVisual Closure::
Ability to identify an incomplete figure when Ability to identify an incomplete figure when only parts of it are presentonly parts of it are present
Visual MemoryVisual Memory:: Ability to recall dominant features of one Ability to recall dominant features of one
stimulus item or remember sequence of stimulus item or remember sequence of several itemsseveral items
Chosen because at time test was developed, Chosen because at time test was developed, they were the most prominent theoretical they were the most prominent theoretical constructs in the literatureconstructs in the literature
MVPT (5)MVPT (5) Target PopulationTarget Population
Standardized on a sample of 4 children Standardized on a sample of 4 children aged 8 years old.aged 8 years old.
A revised edition was developed for use A revised edition was developed for use with the adult population (Bouska & with the adult population (Bouska & Kwatny, 1983)Kwatny, 1983)
MVPT-R was published in 1996 by the MVPT-R was published in 1996 by the original authorsoriginal authors Addresses issues of incomplete and Addresses issues of incomplete and
outdated normative data (increasing ages of outdated normative data (increasing ages of children to 9-11 years)children to 9-11 years)
Also, added 4 more itemsAlso, added 4 more items NO re-standardization from the 1972 dataNO re-standardization from the 1972 data
MVPT (6)MVPT (6)
Administration ProceduresAdministration Procedures Administered individually/ approximately Administered individually/ approximately
10 minutes10 minutes Well-lit, distraction free environmentWell-lit, distraction free environment Testing books in the client’s midlineTesting books in the client’s midline Examiner on left or right client, providing Examiner on left or right client, providing
clear informationclear information If client has hemianopsia, examiner If client has hemianopsia, examiner
should sit on client’s intact sideshould sit on client’s intact side
MVPT (7)MVPT (7) 40 multiple choice questions each with a 40 multiple choice questions each with a
stimulus and 4 possible answersstimulus and 4 possible answers Assessor points to each – “look at this”Assessor points to each – “look at this” Assessor then points to 4 potential Assessor then points to 4 potential
responses – “find it here”responses – “find it here” Client points to his/her responseClient points to his/her response ScoringScoring::
Assessor circles client’s responses on scoring Assessor circles client’s responses on scoring sheetsheet
Only correct answers are recordedOnly correct answers are recorded Raw score is calculated (sum of correct answers)Raw score is calculated (sum of correct answers)
MVPT (8)MVPT (8)
Motor-Free Assessment of Visual Motor-Free Assessment of Visual PerceptionPerception Other tests purport to measure visual Other tests purport to measure visual
perception but have a motor component perception but have a motor component (i.e.: drawing) which acts as a (i.e.: drawing) which acts as a confounder for measuring visual confounder for measuring visual perception.perception.
Practically most perceptual abilities are Practically most perceptual abilities are integrated with motor systems’ abilitiesintegrated with motor systems’ abilities
MVPT (9)MVPT (9)
Not comprehensive Not comprehensive – Body – Body Scheme and Right/Left Scheme and Right/Left Discrimination are Discrimination are notnot assessed assessed Recommended to not be used Recommended to not be used
exclusively to assess visual perceptual exclusively to assess visual perceptual abilitiesabilities
Recommended that it be used with Recommended that it be used with measures of functional performance (i.e. measures of functional performance (i.e. FIM)FIM)
MVPT (10)MVPT (10)
Many researchers have attested that Many researchers have attested that seeing an object alone is of little seeing an object alone is of little practical use if you can’t perceive its practical use if you can’t perceive its shape, location, movement, or colourshape, location, movement, or colour
MVPT: Bottom-Up MVPT: Bottom-Up ProcessingProcessing
MVPT assesses visual perception by MVPT assesses visual perception by testing clients on domains of function testing clients on domains of function such as figure-ground discrimination, such as figure-ground discrimination, etc.etc.
The authors of the test argue that these The authors of the test argue that these are the most prominent theoretical are the most prominent theoretical domains of visual perception when the domains of visual perception when the test was designed.test was designed.
MVPT: Bottom-Up MVPT: Bottom-Up Processing (2)Processing (2)
However, the scores from each However, the scores from each domain are added together, resulting domain are added together, resulting in a single global score which means in a single global score which means that the ability for the client to that the ability for the client to perform in any one domain is lost. perform in any one domain is lost.
Brown, Rodger, and Davis (2003) Brown, Rodger, and Davis (2003) argue that this may mean that the argue that this may mean that the test therefore has little practical or test therefore has little practical or clinical use.clinical use.
MVPT: Bottom-Up MVPT: Bottom-Up Processing (3)Processing (3)
The authors state that it is not The authors state that it is not comprehensive (it does not measure comprehensive (it does not measure body scheme or right/left body scheme or right/left discrimination)discrimination)
The MVPT was designed as a general The MVPT was designed as a general screening and can serve this purpose screening and can serve this purpose by looking at skills in several bottom-by looking at skills in several bottom-up processesup processes
MVPT: Top-Down MVPT: Top-Down ProcessingProcessing
MVPT does not really assess top-down MVPT does not really assess top-down processing of visual information processing of visual information
The results can be used to predict The results can be used to predict possible functionpossible function
The Introduction to the test states that The Introduction to the test states that the test should be used the test should be used in in conjunctionconjunction with functional with functional assessment to determine the true state assessment to determine the true state of their visual perceptual abilities.of their visual perceptual abilities.
MVPT: Top-Down MVPT: Top-Down Processing (2)Processing (2)
Therefore, using other assessment Therefore, using other assessment tools to look at Top-down processing tools to look at Top-down processing such as the Functional Independence such as the Functional Independence Measure (FIM) is essential for Measure (FIM) is essential for predicting functioning in clients.predicting functioning in clients.
MVPT: Luria’s Model of MVPT: Luria’s Model of Brain FunctioningBrain Functioning
Recognizes the cooperation & Recognizes the cooperation & integration of various systems in brain integration of various systems in brain functioning functioning
MVPT assesses visual perception in a MVPT assesses visual perception in a motor-free way motor-free way
Systems involving perception are Systems involving perception are interrelated with other systems such as interrelated with other systems such as the motor system. the motor system.
Assessing Assessing visual perceptionvisual perception occurs at occurs at the 2nd functional unit in Luria’s model.the 2nd functional unit in Luria’s model.
MVPT: Luria’s Model of MVPT: Luria’s Model of Brain Functioning (2)Brain Functioning (2)
RECALL:RECALL: 3 increasing levels of integration in each lobe 3 increasing levels of integration in each lobe
involved in this unit.involved in this unit. Registration of visual stimuli occurs at the primary Registration of visual stimuli occurs at the primary
areaarea The secondary area turns sensations into perceptions.The secondary area turns sensations into perceptions. MVPT measures visual perception fitting here in MVPT measures visual perception fitting here in
Luria’s model. Luria’s model. The tertiary area involves complex integration of The tertiary area involves complex integration of
these percepts.these percepts. MVPT does not assess its integration with other MVPT does not assess its integration with other
systems, therefore, such visual perceptual abilities as systems, therefore, such visual perceptual abilities as interpreting non-verbal communication (ie. interpreting non-verbal communication (ie. smile=happiness),is not assessed.smile=happiness),is not assessed.
MVPT: Luria’s Model of MVPT: Luria’s Model of Brain Functioning (3)Brain Functioning (3)
Scoring in the MVPT are dichotomous; ie. Scoring in the MVPT are dichotomous; ie. either right or wrong either right or wrong
Makes it difficult to assess the Makes it difficult to assess the complexities of perceptioncomplexities of perception Dichotomy limits MVPT from assessing some Dichotomy limits MVPT from assessing some
types of agnosiatypes of agnosia AgnosiaAgnosia - Impaired object recognition not - Impaired object recognition not related to visual lossrelated to visual loss Can generate an adequate internal Can generate an adequate internal
representation of a stimulus, but cannot representation of a stimulus, but cannot recognize itrecognize it
MVPT: Luria’s Model of MVPT: Luria’s Model of Brain Functioning (4)Brain Functioning (4)
Associative AgnosiaAssociative Agnosia Failure to recognize Failure to recognize meaningmeaning of what is of what is
perceivedperceived Ex. A client with an ABI recognizes circles Ex. A client with an ABI recognizes circles
from squares, but does he know that what he from squares, but does he know that what he is looking at is a circle/shape? is looking at is a circle/shape?
Ability to match objects is assessed in the Ability to match objects is assessed in the MVPT (clients w/ Associative are able to do)MVPT (clients w/ Associative are able to do)
Associative is not directly assessed since it Associative is not directly assessed since it does not assess whether clients actually does not assess whether clients actually understand the meaning behind what they understand the meaning behind what they are perceivingare perceiving
MVPT: Luria’s Model of MVPT: Luria’s Model of Brain Functioning (5)Brain Functioning (5)
Apperceptive AgnosiaApperceptive Agnosia Failure to even perceive Failure to even perceive
visual stimuli visual stimuli Able to sense and register Able to sense and register
sensory stimuli from the sensory stimuli from the environment but cannot environment but cannot connect sensations to connect sensations to actual percepts. actual percepts.
Thus the ability to Thus the ability to perceive is deficient. perceive is deficient.
MVPT: Luria’s Model of MVPT: Luria’s Model of Brain Functioning (6)Brain Functioning (6)
MVPT assesses visual apperceptive MVPT assesses visual apperceptive agnosia indirectly agnosia indirectly
The domains the MVPT assesses The domains the MVPT assesses determine whether or not clients can determine whether or not clients can perceive stimuli from the environmentperceive stimuli from the environment
However, MVPT’s dichotomous scoring However, MVPT’s dichotomous scoring does not allow clinicians to does not allow clinicians to understandunderstand the reasons for their answersthe reasons for their answers
MVPT: Luria’s Model of MVPT: Luria’s Model of Brain Functioning (7)Brain Functioning (7)
Not congruent with visual perception Not congruent with visual perception having many shades of grey with the having many shades of grey with the levels of processing ranging in complexity levels of processing ranging in complexity of integration of integration Researchers found that clients’ who perform Researchers found that clients’ who perform
well on tests assessing visual processing of well on tests assessing visual processing of inanimate objects (as does MVPT), perform inanimate objects (as does MVPT), perform poorly on tests that assess animate objects poorly on tests that assess animate objects (such as the Benton Facial Recognition) (such as the Benton Facial Recognition) (Duchaine et al., 2003)(Duchaine et al., 2003)
This questions the validity of the MVPT and This questions the validity of the MVPT and the generalizability of the findings to all the generalizability of the findings to all visual stimulivisual stimuli
Neuroanatomy of Neuroanatomy of Visual PerceptionVisual Perception
The MVPT tests clients on perceptual The MVPT tests clients on perceptual abilities that may result from abilities that may result from damage to different brain regionsdamage to different brain regions
Figure GroundFigure Ground Lesion: non-dominant occipital lobeLesion: non-dominant occipital lobe
Spatial RelationshipsSpatial Relationships Tertiary zone perceptual deficit: Tertiary zone perceptual deficit:
related to impaired depth perception related to impaired depth perception (lesion: right hemisphere visual (lesion: right hemisphere visual cortex)cortex)
Neuroanatomy of Neuroanatomy of Visual Perception (2)Visual Perception (2)
Visual DiscriminationVisual Discrimination Parietal and temporal lobe damage. A Parietal and temporal lobe damage. A
disorder in visual discrimination disorder in visual discrimination involves an inability to attend to slight involves an inability to attend to slight variations in formvariations in form. .
Therefore, by asking the client to Therefore, by asking the client to match shapes tests their ability to match shapes tests their ability to tell the difference between different tell the difference between different forms.forms.
MVPT Findings: MVPT Findings: Driving AbilitiesDriving Abilities
Safe driving requires the driver to Safe driving requires the driver to integrate complex visual processing integrate complex visual processing skillsskills
Mazer et al. argue that visual perceptual Mazer et al. argue that visual perceptual skills such as figure-ground skills such as figure-ground discrimination, visual discrimination, discrimination, visual discrimination, spatial relations (all tested by the MVPT) spatial relations (all tested by the MVPT) determine the ability to notice and react determine the ability to notice and react to objects in the visual field which is to objects in the visual field which is required when driving.required when driving.
MVPT Findings: MVPT Findings: Driving Abilities (2)Driving Abilities (2)
People who failed the on-road driving People who failed the on-road driving test performed more poorly on the test performed more poorly on the MVPT than those who passed in people MVPT than those who passed in people who had suffered a stroke (Mazer et al.)who had suffered a stroke (Mazer et al.)
However, the scores were not highly However, the scores were not highly predictive of a pass. predictive of a pass.
MVPT does not look at colour agnosia, MVPT does not look at colour agnosia, simultagnosia, metamorphosia.simultagnosia, metamorphosia.
MVPT: Driving AbilitiesMVPT: Driving Abilities
Driving, in addition to perceptual Driving, in addition to perceptual skills, requires judgment, and skills, requires judgment, and behavioural and cognitive skills that behavioural and cognitive skills that the MVPT does not test. the MVPT does not test.
However, the MVPT seems to cover However, the MVPT seems to cover many of the visual perceptual skills many of the visual perceptual skills required for driving.required for driving.
MVPT: Driving Abilities (2)MVPT: Driving Abilities (2)
Visual DiscriminationVisual Discrimination Need to see shapes to distinguish Need to see shapes to distinguish
signs and cars from other moving signs and cars from other moving objects, see stop lights, etc.objects, see stop lights, etc.
Figure GroundFigure Ground To see lines on the road, objects on To see lines on the road, objects on
the road that may be hazardsthe road that may be hazards
MVPT: Driving Abilities (3)MVPT: Driving Abilities (3)
Visual MemoryVisual Memory To find one’s way around, follow To find one’s way around, follow
landmarks and directionslandmarks and directions Spatial RelationshipsSpatial Relationships
Ability to avoid hazards, find way Ability to avoid hazards, find way around, change lanes, etcaround, change lanes, etc
Professional OpinionProfessional Opinion Mandy LoweMandy Lowe
Toronto Rehabilitation InstituteToronto Rehabilitation Institute
Important to build rapport to determine which Important to build rapport to determine which MVPT to utilizeMVPT to utilize Level of difficulty varies for eachLevel of difficulty varies for each
Scoring – sum of all parts:Scoring – sum of all parts: Does not inform interventionDoes not inform intervention Norms are based on overall score (all domains)Norms are based on overall score (all domains)
Easy to transport; bring to bedsideEasy to transport; bring to bedside Consent – risks and benefits:Consent – risks and benefits:
Results can be upsettingResults can be upsetting Could also be less upsetting than finding out on a Could also be less upsetting than finding out on a
functional taskfunctional task
Loewenstein Occupational Loewenstein Occupational Therapy Cognitive Therapy Cognitive
Assessment Assessment Authors: Itzkovich, M., Averbuch, S., & Authors: Itzkovich, M., Averbuch, S., &
Elazar, B.Elazar, B. 19741974
Loewenstein Loewenstein Occupational Therapy Occupational Therapy Cognitive Assessment Cognitive Assessment
(LOTCA)(LOTCA) PurposePurpose Evaluating patients who have experienced brain-Evaluating patients who have experienced brain-
injuries (ie. traumatic head injuries, CVA, injuries (ie. traumatic head injuries, CVA, tumours)tumours)
Provides an initial profile of the cognitive Provides an initial profile of the cognitive abilities of an individual; used as a starting point abilities of an individual; used as a starting point for OT intervention as well as a screening test for OT intervention as well as a screening test for further assessmentfor further assessment
Provides a valid profile of a client's abilities and Provides a valid profile of a client's abilities and a measurable assessment of specific deficits to a measurable assessment of specific deficits to help plan treatment.help plan treatment.
LOTCA (2)LOTCA (2)
FocusFocus Four areas; 20 subtestsFour areas; 20 subtests
OrientationOrientation Visual & Spatial Perception (6 Visual & Spatial Perception (6
subtests)subtests) Visuomotor OrganizationVisuomotor Organization Thinking OperationsThinking Operations
Target PopulationsTarget Populations Paediatric (Paediatric ( 6 y/o) 6 y/o) AdultAdult
Evaluation ApproachEvaluation Approachof LOTCAof LOTCA
30-45 min to administer 30-45 min to administer (for entire test)(for entire test) ““Perception”Perception” is the is the activeactive process of: process of:
Searching for the corresponding info,Searching for the corresponding info, Distinguishing essential features of an object,Distinguishing essential features of an object, Comparing the features with each other,Comparing the features with each other, Creating appropriate hypotheses,Creating appropriate hypotheses, Comparing these hypotheses with original Comparing these hypotheses with original
datadata
(Luria, 1973)(Luria, 1973)
Evaluation ApproachEvaluation Approachof LOTCA (2)of LOTCA (2)
Administration of LOTCAAdministration of LOTCA ComponentsComponents: cards, pictures, scissors & : cards, pictures, scissors &
paper, picture “puzzle”paper, picture “puzzle” Important to eliminate influence on the Important to eliminate influence on the
client during the testclient during the test ScoringScoring: 1 (low) – 4 (high) : 1 (low) – 4 (high) [ordinal][ordinal]
based on client’s ability for based on client’s ability for (independent) success with each test(independent) success with each test
subtests can be altered to assist clientsubtests can be altered to assist client normative scores availablenormative scores available
Piaget’s Theory of Piaget’s Theory of Cognitive DevelopmentCognitive Development
Jean Piaget (1896-1980)Jean Piaget (1896-1980) Developmental psychologyDevelopmental psychology
InterestInterest “how we come “how we come
to know”to know” Ability to do “abstract Ability to do “abstract
symbolic reasoning”symbolic reasoning”
Piaget’s “Cognitive Piaget’s “Cognitive Development” (2)Development” (2)
Began to work with children and Began to work with children and investigate their thought processesinvestigate their thought processes
Noted young children’s answers Noted young children’s answers were were qualitativelyqualitatively different than different than those of older childrenthose of older children
Younger children answered Younger children answered differently because they thought differently because they thought distinctively, not because they distinctively, not because they were less knowledgeablewere less knowledgeable
Piaget’s “Cognitive Piaget’s “Cognitive Development” (3)Development” (3)
Two aspects to Piaget’s theory:Two aspects to Piaget’s theory:1. Process of coming to know, and1. Process of coming to know, and
2. Stages we move through as we gradually 2. Stages we move through as we gradually acquire this abilityacquire this ability
Process of Cognitive Development:Process of Cognitive Development: ““Intelligence” = how an organism adapts Intelligence” = how an organism adapts
to its environmentto its environment Believed behaviour is controlled through Believed behaviour is controlled through
schemesschemes
Piaget’s “Cognitive Piaget’s “Cognitive Development” (4)Development” (4)
““Equilibration” = drive to obtain Equilibration” = drive to obtain balance between schemes and the balance between schemes and the environmentenvironment
Assimilation Assimilation Transforming and placing the environment Transforming and placing the environment
in pre-existing cognitive structuresin pre-existing cognitive structures AccommodationAccommodation
Changing cognitive structures in order to Changing cognitive structures in order to accept something from the environmentaccept something from the environment
Piaget’s “Cognitive Piaget’s “Cognitive Development” (5)Development” (5)
SchemesSchemes
(more complex)(more complex)
StructuresStructures
(more(morecomplex)complex)
HierarchyHierarchy
Luria’s Theory of Luria’s Theory of Functional SystemsFunctional Systems
Brain = Organized systemBrain = Organized system 3 “Blocks”3 “Blocks”
1. Brainstem1. Brainstem
2. Area posterior to central sulcus2. Area posterior to central sulcus
3. Area anterior to central sulcus3. Area anterior to central sulcus
Luria’s Luria’s “Functional Systems” (2)“Functional Systems” (2) Functional Units (‘Blocks’)Functional Units (‘Blocks’)
Interact with one another to produce Interact with one another to produce optimal performance on a taskoptimal performance on a task
11stst Functional Unit Functional Unit Role in attention and memory, in part by Role in attention and memory, in part by
processing information according to its processing information according to its salience (relevance, importance and salience (relevance, importance and novelty)novelty)
Luria’s Luria’s “Functional Systems” (3)“Functional Systems” (3) 22ndnd Functional Unit Functional Unit
Primary role in Primary role in perceptionperception Registers & integrates sensory Registers & integrates sensory
information into perceptionsinformation into perceptions 33rdrd Functional Unit Functional Unit
Executive controlExecutive control Control over complex sequences of Control over complex sequences of
activityactivity
Influence of Piaget & Influence of Piaget & Luria’s Theories on Luria’s Theories on
LOTCA LOTCA PiagetPiaget
Young Young vsvs old children; qualitative old children; qualitative vs vs quantitativequantitative
Use of schemes, assimilation & Use of schemes, assimilation & accommodationaccommodation
Schemes Schemes Structures Structures Hierarchy Hierarchy LuriaLuria
22ndnd Functional Unit Functional Unit: primary role in perception: primary role in perception 33rdrd Functional Unit Functional Unit: executive functions: executive functions Interplay between Functional UnitsInterplay between Functional Units
Domains of the LOTCADomains of the LOTCA
6 Subtests6 Subtests
Visual Identification of ObjectsVisual Identification of Objects
Visual Identification of ShapesVisual Identification of Shapes
Overlapping FiguresOverlapping Figures
Object ConstancyObject Constancy
Spatial PerceptionSpatial Perception
PraxisPraxis
Two Types of Two Types of Visual Testing AreasVisual Testing Areas
Visual Object AgnosiaVisual Object Agnosia – inability – inability to recognize objects presented to recognize objects presented visually, although primary visual visually, although primary visual skills are intactskills are intact
Visual Spatial AgnosiaVisual Spatial Agnosia – defect in – defect in perceiving spatial relationships perceiving spatial relationships between objects, or objects and selfbetween objects, or objects and self
Visual Identification Visual Identification of Objectsof Objects
What It’s MeasuringWhat It’s Measuring Associative Visual Agnosia (some Aperceptive Associative Visual Agnosia (some Aperceptive
Agnosia)Agnosia)
ExampleExample: individual with associative agnosia, : individual with associative agnosia, able to copy pictures but able to copy pictures but cannotcannot recognize recognize objectobject
ExampleExample: Name these common : Name these common animalsanimals
Visual Visual Identification Identification of Objects (2)of Objects (2)
Neuroanatomical causeNeuroanatomical cause Lesions typically located in right Lesions typically located in right
hemisphere in posterior multimodal hemisphere in posterior multimodal association areaassociation area
How to AdministerHow to Administer Client shown 8 cards with common Client shown 8 cards with common
objects (objects (chair, teapot, watch, key, chair, teapot, watch, key, shoe, bicycle, scissors, glasses)shoe, bicycle, scissors, glasses)
Name objectsName objects
Visual Identification Visual Identification of Objects (3)of Objects (3)
Visual Identification Visual Identification of Objects (4)of Objects (4)
If Client is Having DifficultyIf Client is Having Difficulty Person has global or Person has global or
receptive/expressive aphasiareceptive/expressive aphasia
Problems with TestProblems with Test Does not test for Prosopagnosia (inability Does not test for Prosopagnosia (inability
to identify known individuals by face)to identify known individuals by face) Trial and error of matching boardTrial and error of matching board Unsure what test can be measuringUnsure what test can be measuring
Visual Identification Visual Identification of Shapesof Shapes
What it is MeasuringWhat it is Measuring Visual AgnosiaVisual AgnosiaExampleExample: Individual unable to copy and : Individual unable to copy and
match match
simple forms (letters) and geometric simple forms (letters) and geometric shapesshapes
Visual Identification Visual Identification of Shapes (2)of Shapes (2)
Neuroanatomical CauseNeuroanatomical Cause Lesions typically located in right Lesions typically located in right
hemisphere in posterior multimodal hemisphere in posterior multimodal association areaassociation area
How to AdministerHow to Administer Client shown 8 cards with solid Client shown 8 cards with solid
geometric shapes (geometric shapes (square, triangle, square, triangle, circle, rectangle, diamond, semi-circle, circle, rectangle, diamond, semi-circle, trapezoid, hexagon)trapezoid, hexagon)
Name objectsName objects
Visual Identification Visual Identification of Shapes (3)of Shapes (3)
If Client is Having DifficultyIf Client is Having Difficulty Client cannot verbally name shape due to Client cannot verbally name shape due to
aphasia, expressive problems, or aphasia, expressive problems, or educational backgroundeducational background
Use matching boardUse matching board
Problems with TestProblems with Test Test consists of four easy shapes and four Test consists of four easy shapes and four
more complex onesmore complex ones However, a score of ‘4’ can be attained if However, a score of ‘4’ can be attained if
patient identifies shapes by naming and/or patient identifies shapes by naming and/or matchingmatching
Overlapping FiguresOverlapping Figures
What It’s MeasuringWhat It’s Measuring Figure-Ground Figure-Ground
Neuroanatomical CauseNeuroanatomical Cause Damage/lesion to non-dominant Damage/lesion to non-dominant
occipital lobeoccipital lobe
Overlapping Figures Overlapping Figures (2)(2)
How to AdministerHow to Administer Two cards with three overlapping figures Two cards with three overlapping figures
on each card (a. banana, pear, apple; b. on each card (a. banana, pear, apple; b. pliers, hoe, saw)pliers, hoe, saw)
Client is asked to name all figures seen on Client is asked to name all figures seen on cardcard
If Client is Having DifficultyIf Client is Having Difficulty Board is shown with 6 figures (3 are figures Board is shown with 6 figures (3 are figures
on the card, 3 are different figures)on the card, 3 are different figures) Client has to point to what figures are seen Client has to point to what figures are seen
on the cardon the card
Overlapping Figures Overlapping Figures (3)(3)
Problems with TestProblems with Test Does notDoes not::
Incorporate real, ”everyday”Incorporate real, ”everyday”
images/pictures, and picturesimages/pictures, and pictures
with colourwith colour Include objects that have Include objects that have
more similar features to onemore similar features to one
anotheranother
ExampleExample: What objects do you : What objects do you
see?see?
Object ConstancyObject Constancy
What It’s MeasuringWhat It’s Measuring Form Constancy DysfunctionForm Constancy Dysfunction
Object Constancy (2)Object Constancy (2) Neuroanatomical CauseNeuroanatomical Cause
Lesion in right parietal, temporal, and occipital lobe Lesion in right parietal, temporal, and occipital lobe areasareas
How to AdministerHow to Administer Client shown photographs of objects taken from Client shown photographs of objects taken from
unusual angles (car, hammer, telephone, fork)unusual angles (car, hammer, telephone, fork) Asked what is seen in photographAsked what is seen in photograph
If Client is Having DifficultyIf Client is Having Difficulty If client has aphasia, he/she is asked to match the If client has aphasia, he/she is asked to match the
picture to the one that suits the big one on a board picture to the one that suits the big one on a board that has 4 picturesthat has 4 pictures
Object Constancy (3)Object Constancy (3) Problems with TestProblems with Test
Does not test for letters and numbersDoes not test for letters and numbers
Example: Point out letters O, Q, and D
Spatial PerceptionSpatial Perception What It’s MeasuringWhat It’s Measuring
R-L Discrimination R-L Discrimination SomatogonosiaSomatogonosia Position in Space DysfunctionPosition in Space Dysfunction
Neuroanatomical CauseNeuroanatomical Cause Typically parietal lobe and/or posterior Typically parietal lobe and/or posterior
temporal lobetemporal lobe Left hemisphereLeft hemisphere
Spatial Perception (2)Spatial Perception (2)
How to AdministerHow to Administera) OT asks client to perform simple a) OT asks client to perform simple
movements (recognize directions movements (recognize directions on themselves)on themselves)
b) Orientation between objects (box b) Orientation between objects (box & pencil)& pencil)
c) Recognizing directions on person c) Recognizing directions on person in front of themin front of them
Spatial Perception (3)Spatial Perception (3)
Problems with TestProblems with Test Client with language barrier or severe Client with language barrier or severe
receptive aphasia may not understand receptive aphasia may not understand instructionsinstructions
Clients with arthritis and/or poor fine Clients with arthritis and/or poor fine motor abilities may have difficultiesmotor abilities may have difficulties Items with larger surface-areasItems with larger surface-areas
PraxisPraxis What It’s MeasuringWhat It’s Measuring
Praxis = motor planningPraxis = motor planning Measures the ability to execute motor Measures the ability to execute motor
functionsfunctions Associative visual agnosiaAssociative visual agnosia
Anatomical CauseAnatomical Cause Motor apraxia = caused by lesion to the Motor apraxia = caused by lesion to the
premotor cortex on the opposite side of premotor cortex on the opposite side of the affected limbthe affected limb
Frontal Lobe Frontal Lobe motor planning & motor planning & executive executive
functioningfunctioning
Praxis (2)Praxis (2)
How to AdministerHow to Administera) a) Motor imitationMotor imitation – client imitates – client imitates
movements by experimenter (hand to movements by experimenter (hand to ear/head/shoulder)ear/head/shoulder)
b) b) Object utilizationObject utilization – experimenter presents – experimenter presents pairs of objects and asks client how to use pairs of objects and asks client how to use them (scissors & paper, envelope & paper)them (scissors & paper, envelope & paper)
c) c) Symbolic actionsSymbolic actions – client is asked what – client is asked what they would do when they smell flower, they would do when they smell flower, open door with keyopen door with key
Praxis (3)Praxis (3)
Problems with TestProblems with Test If receptive aphasia exists client may If receptive aphasia exists client may
have difficulty with understanding or have difficulty with understanding or following instructionsfollowing instructions
Possibility exists that lesion to frontal Possibility exists that lesion to frontal lobe may be the (major) cause of having lobe may be the (major) cause of having difficulty with the test; may not be a difficulty with the test; may not be a perceptual issueperceptual issue
Motor dysfunctionMotor dysfunction
What’s Missing?What’s Missing? Test for Test for SimultagnosiaSimultagnosia? ?
Patient cannot interpret visual stimulus Patient cannot interpret visual stimulus as a wholeas a whole
Could only point out individual letters or Could only point out individual letters or featuresfeatures
Test for Test for Colour AgnosiaColour Agnosia?? Test for Test for MetamorphosiaMetamorphosia??
Object may be recognized accurately, Object may be recognized accurately, but appears larger or smaller than it but appears larger or smaller than it actually isactually is
Potential problems with ADL functioningPotential problems with ADL functioning
Potential DifficultiesPotential Difficulties Cultural barriers (i.e. person may not Cultural barriers (i.e. person may not
be familiar with the object being be familiar with the object being shown)shown)
Language barriers (ESL-individual may Language barriers (ESL-individual may know what object is, but cannot know what object is, but cannot express in English) express in English)
Some subtests would not be feasible to Some subtests would not be feasible to adapt for persons with receptive/ adapt for persons with receptive/ expressive aphasia, and individuals expressive aphasia, and individuals with fine/gross motor difficultieswith fine/gross motor difficulties
Potential Difficulties (2)Potential Difficulties (2)
Questionable if test can really assess how Questionable if test can really assess how person would perform in actual situations person would perform in actual situations (top-down component should be added)(top-down component should be added)
Underlying problems, such as unilateral Underlying problems, such as unilateral spatial neglect, may skew results if spatial neglect, may skew results if unknown by examiner (Katz, 1999)unknown by examiner (Katz, 1999)
Stewart & Schindler found that individuals Stewart & Schindler found that individuals without brain injury did not attain a perfect without brain injury did not attain a perfect score on the LOTCAscore on the LOTCA
LOTCA Findings: LOTCA Findings: Dressing OneselfDressing Oneself
Successful and efficient dressing Successful and efficient dressing requires utilizing integration of requires utilizing integration of perceptual skillsperceptual skills
One’s abilities in visual perceptual One’s abilities in visual perceptual skills are related to particular aspects skills are related to particular aspects of identifying and selecting specific of identifying and selecting specific articles of clothingarticles of clothing
LOTCA Findings: LOTCA Findings: Dressing Oneself (2)Dressing Oneself (2)
Visual Identification of Objects Visual Identification of Objects && Visual Identification of ShapesVisual Identification of Shapes Inability to find clothes (identifying Inability to find clothes (identifying
shape of pants, belt, ties, long-sleeved shape of pants, belt, ties, long-sleeved vs short-sleeved)vs short-sleeved)
Recognition of clothing – if individual Recognition of clothing – if individual cannot recognize the article of clothing, cannot recognize the article of clothing, he/she may not know its purpose and he/she may not know its purpose and how to wear it (where do socks go on how to wear it (where do socks go on one’s body?)one’s body?)
LOTCA Findings: LOTCA Findings: Dressing Oneself (3)Dressing Oneself (3)
Overlapping FiguresOverlapping Figures Difficulty locating clothes in closet, Difficulty locating clothes in closet,
dresser (socks/underwear in drawer)dresser (socks/underwear in drawer) Experience increased difficulties if Experience increased difficulties if
clothes are similar in colour to other clothes are similar in colour to other articles of clothing and/or where they articles of clothing and/or where they are stored (closet, drawer)are stored (closet, drawer)
LOTCA Findings: LOTCA Findings: Dressing Oneself (4)Dressing Oneself (4)
Object ConstancyObject Constancy Difficulty recognizing clothes/items in Difficulty recognizing clothes/items in
various arrangements (ie. shirt folded various arrangements (ie. shirt folded vsvs on hanger)on hanger)
Orientate clothing incorrectly (put on Orientate clothing incorrectly (put on inside out, backwards)inside out, backwards)
Select “wrong” items Select “wrong” items wear spouse’s wear spouse’s clothesclothes
LOTCA Findings: LOTCA Findings: Dressing Oneself (5)Dressing Oneself (5)
Spatial PerceptionSpatial Perception Put shoes on wrong feet; difficulties Put shoes on wrong feet; difficulties
putting sweater on (ie. video with putting sweater on (ie. video with gentleman)gentleman)
Unawareness of own body parts may Unawareness of own body parts may exist and client may have difficulty with exist and client may have difficulty with concepts related to body positions and concepts related to body positions and deciphering between ‘left’ and ‘right’deciphering between ‘left’ and ‘right’
LOTCA Findings: LOTCA Findings: Dressing Oneself (6)Dressing Oneself (6)
PraxisPraxis May have difficulty putting a t-shirt on May have difficulty putting a t-shirt on
(bringing hands to head)(bringing hands to head) Confusion with respect to knowing how Confusion with respect to knowing how
to put a belt through the pant loopsto put a belt through the pant loops
Professional OpinionProfessional Opinion Mandy LoweMandy Lowe
Toronto Rehabilitation InstituteToronto Rehabilitation Institute Important to tread carefully and use the Important to tread carefully and use the
appropriate test at the appropriate level of appropriate test at the appropriate level of functioning (frustration, self-esteem issues)functioning (frustration, self-esteem issues)
Identifies difficulties in real life (ecological Identifies difficulties in real life (ecological validity)validity)
Correlated with FIM & Mini-MentalCorrelated with FIM & Mini-Mental No overall score; need motor control/abilitiesNo overall score; need motor control/abilities Doesn’t touch much on processing speedDoesn’t touch much on processing speed Need table/area to move items aroundNeed table/area to move items around
Professional Opinion (2)Professional Opinion (2)
Nicky BrookesNicky BrookesHospital for Sick ChildrenHospital for Sick Children Paediatrics; prefers LOTCA for 10-16 y/oPaediatrics; prefers LOTCA for 10-16 y/o However, she feels the variation in scores at However, she feels the variation in scores at
the ends of the age-range makes it less the ends of the age-range makes it less reliable/valid and prefers LOTCA for 13 & 14 reliable/valid and prefers LOTCA for 13 & 14 y/oy/o
‘‘Visual & Spatial Perception’ section in LOTCA Visual & Spatial Perception’ section in LOTCA is similar to other testsis similar to other tests
Believes it is a valid and reliable assessment Believes it is a valid and reliable assessment tool; easy to administer; enjoys using ittool; easy to administer; enjoys using it
LOTCALOTCA MVPTMVPT
ValidityValidity Good construct Good construct validityvalidity
(Katz et al., 2000; (Katz et al., 2000; Su et al.,; & Katz et Su et al.,; & Katz et al., 1989)al., 1989) Ecological Ecological validity: some validity: some pictures of real-life pictures of real-life objects (e.g.: cars, objects (e.g.: cars, eating utensils, eating utensils, etc.)etc.)
Versions keep Versions keep changing therefore changing therefore little up-to-date little up-to-date research on validity.research on validity. Less ecologically Less ecologically valid: abstract valid: abstract shapes, function not shapes, function not directly addressed.directly addressed.
Psychometrics – LOTCA & Psychometrics – LOTCA & MVPTMVPT
LOTCALOTCA MVPTMVPTReliabilitReliabilit
yy Inter-rater = Inter-rater = ranged ranged from .82 to .97 from .82 to .97 (Katz et al., (Katz et al., 1989)1989) Internal Internal consistency consistency = .85-.95 (Katz = .85-.95 (Katz et al., 1989)et al., 1989) Test-Retest=Test-Retest=?? Score sheet Score sheet contains space contains space to write to write additional additional comments/ comments/ observations observations
Versions keep Versions keep changing therefore little changing therefore little up-to-date research on up-to-date research on reliabilityreliability Moderate test-retest Moderate test-retest reliability for the MVPT-reliability for the MVPT-R was found with more R was found with more stability in visual stability in visual perceptual scores for perceptual scores for children with learning children with learning disabilities (Burtner et disabilities (Burtner et al., 2002)al., 2002) Inter-rater Inter-rater percentages of percentages of agreement were high agreement were high during pilot testing of during pilot testing of the MVPT-R (Burtner et the MVPT-R (Burtner et al., 2002)al., 2002)
LOTCALOTCA MVPTMVPT
ClinicaClinical l
UtilityUtility
Children (>6) and Children (>6) and adults who have adults who have brain injury, CCI, brain injury, CCI, and CVAand CVA LOTCA-G LOTCA-G developed for developed for geriatric population geriatric population (Itzkovich et al., (Itzkovich et al., 1996)1996) Easy to administer Easy to administer (no training (no training required)required) Can perform in a Can perform in a variety of clinical variety of clinical settingssettings Subtests scored Subtests scored separately so OT separately so OT can know what kind can know what kind of treatment of treatment intervention is intervention is requiredrequired
Motor-free; good for Motor-free; good for clients with motor clients with motor impairmentsimpairments Cannot isolate domains Cannot isolate domains thus limits specificity of thus limits specificity of intervention (Brown et al., intervention (Brown et al., 2003)2003) Short in length, quick to Short in length, quick to administer (Burtner et al., administer (Burtner et al., 2002)2002) Provides detailed, Provides detailed, objective and standardized objective and standardized information that can be information that can be readily communicated to readily communicated to other professionalsother professionals Can be used by any Can be used by any qualified OT or SLP without qualified OT or SLP without having had a specialist having had a specialist training in RPAB training in RPAB administrationadministration
Thank YouThank You
ReferencesReferences Brown, G.T., Rodger, S., & Davis, A. (2003). Motor-free Brown, G.T., Rodger, S., & Davis, A. (2003). Motor-free
Visual Perception Test-Revised: An overview and critique. Visual Perception Test-Revised: An overview and critique. British Journal of Occupational Therapy, 66British Journal of Occupational Therapy, 66(4), 159-167. (4), 159-167.
Burtner, P.A., Ortega, S.G., Morris, C.G., Scott, K., & Burtner, P.A., Ortega, S.G., Morris, C.G., Scott, K., & Qualls, C. (2002). Discrimination validity of the Motor-Qualls, C. (2002). Discrimination validity of the Motor-Free Visual Perceptual Test Revised in children with and Free Visual Perceptual Test Revised in children with and without learning disabilities. without learning disabilities. Occupational Therapy Occupational Therapy Journal of Research, 22,Journal of Research, 22, 161-163. 161-163.
Burtner, P.A., Qualls, C., Ortega, S.G., Morris, C.G., & Burtner, P.A., Qualls, C., Ortega, S.G., Morris, C.G., & Scott, K. (2002). Test-retest reliability of the Motor-Free Scott, K. (2002). Test-retest reliability of the Motor-Free Visual Perception Test Revised (MVPT-R) in children with Visual Perception Test Revised (MVPT-R) in children with and without learning disabilities. and without learning disabilities. Physical and Physical and Occupational Therapy, 22Occupational Therapy, 22, 23-36., 23-36.
Kamble, R., Goswami, S., Saigal, J., Sarin, R., & Jalali, R. Kamble, R., Goswami, S., Saigal, J., Sarin, R., & Jalali, R. (2003). Prospective neuro-cognitive assessment (using (2003). Prospective neuro-cognitive assessment (using LOTCA) and quality of life (QOL) and activities of daily LOTCA) and quality of life (QOL) and activities of daily living (ADL) in children with brain tumour treated with living (ADL) in children with brain tumour treated with surgery and localized high-precision radiotherapy. surgery and localized high-precision radiotherapy. The The Indian Journal of Occupational Therapy, 25Indian Journal of Occupational Therapy, 25, 10-12., 10-12.
References (2)References (2) Itzkovich, M., Elazar, B., & Averbuch, S. (1993). LOTCA: Itzkovich, M., Elazar, B., & Averbuch, S. (1993). LOTCA:
Loewenstein occupational therapy cognitive assessment. Loewenstein occupational therapy cognitive assessment. Pequannock, NJ: Maddak Inc.Pequannock, NJ: Maddak Inc.
Katz, N., Itzkovich, M., Averbuch, S., & Elazar, B. (1989). Katz, N., Itzkovich, M., Averbuch, S., & Elazar, B. (1989). Loewenstein Occupational Therapy Cognitive Assessment Loewenstein Occupational Therapy Cognitive Assessment (LOTCA) battery for brain-injured patients: Reliability and (LOTCA) battery for brain-injured patients: Reliability and validity. validity. The American Journal of Occupational Therapy, 43The American Journal of Occupational Therapy, 43, , 184-192.184-192.
Leonard, P., Foxcroft, C., & Kroukamp, T. (1988). Are visual-Leonard, P., Foxcroft, C., & Kroukamp, T. (1988). Are visual-perceptual and visual-motor skills separate abilities? perceptual and visual-motor skills separate abilities? Perceptual and Motor Skills, 67Perceptual and Motor Skills, 67, 423-426., 423-426.
Mazer, B.L., Korner-Bitensky, N.A., & Sofer, S. (1998). Mazer, B.L., Korner-Bitensky, N.A., & Sofer, S. (1998). Predicting ability to drive after stroke. Predicting ability to drive after stroke. Archives of Physical Archives of Physical and Medical Rehabilitation, 79and Medical Rehabilitation, 79, 743-749., 743-749.
Su, C.Y.; Chang, J.J., Chen, H.M., Su, C.J., Chien, T.H., & Huang, Su, C.Y.; Chang, J.J., Chen, H.M., Su, C.J., Chien, T.H., & Huang, M.H. (2000). Perceptual differences between stroke patients M.H. (2000). Perceptual differences between stroke patients with cerebral infarction and intercerebral hemorrhage. with cerebral infarction and intercerebral hemorrhage. Archives of Physical and Medical Rehabilitation, 81Archives of Physical and Medical Rehabilitation, 81, 706-714., 706-714.