Perceptual and cognitive disorder

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Perceptual and cognitive dysfunction SHIVA TIWARI

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Page 1: Perceptual and cognitive disorder

Perceptual and cognitive dysfunction

SHIVA TIWARI

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Perception• Perception is process of integrating sensory stimuli or

impression into the information that is psychologically meaningful. By lezak

• Perception (from the Latin perceptio, percipio) is the organization, identification and interpretation of sensory information in order to represent and understand the environment. All perception involves signals in the nervous system result from physical stimulation of the sense organs. For example, vision involves light striking the retinas of the eyes. Perception is not the passive receipt of these signals ,but can be shaped by learning , memory and expectation.

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• Sensation is just appreciation of stimuli eg hot,cold.

• Perception is that ability to: Select stimuli (needs attention and action) Integrate those stimuli with each other and

with prior information Finally to interpret them

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Cognition

• Cognition is the act or process of knowing including awareness ,reasoning ,judgment ,intuition and memory.

• Executive function also categories sometimes as a cognition and sometimes as metacognition, or higher order cognition

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Assessment

• Need:1. Perception is positively correlated with ability

to perform ADLs.2. Perception is the per-requisite for learning and

rehabilitation .• Clinical indicators of perception deficit are:1. functional loss unexplained by motor, sensory

deficit2. deficient comprehension

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• Aim of perceptual testing:1. is to determine which perceptual abilities are

intact and which are affected.2. How task performance is affected due to

perception deficit.3. To plan realistic and cost effective

intervention

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Factors influencing assessment:

1. Psycho and emotional status2. Coping with disability3. Level of comprehension4. Co-operation, motivation, anxiety.5. Realistic about outcomes6. Family support 7. Environment8. Poor judgment9. Patient’s language skills10. Medications –(drowsiness)11. Fatigue12. Premorbid intellectual level, memory 13. Vision

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• Distinguish between sensory and perceptual problems

• Rule out pure sensory deficits- hearing loss, vision, sensory loss, language, disorientation, lack of comprehension.

• Visual disturbance-visual acuity• visual field defect (hemianopsia)• occulomotor disturbance

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Management

5 approaches to therapy:• Transfer of training approach• Sensory integrative approach• Neuro developmental approach• Functional approach• Cognitive approach

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Retraining approach• Also called transfer of training approach • Described by Averbuch and Katz• Assumption: 1)Disruption in one brain region can have negative impact on brain function as a whole. 2)Practice of one task with particular perceptual requirements will enhance

performance in other tasks with similar perceptual demands. • Young et al demonstrated that training persons with left hemiplegia in block design,

in addition to visual scanning and visual cancellation tasks, resulted in improvements in reading and writing, although no specific training in these areas was offered (Young et al, 1983).

• Neistadt (1995) suggests that a person’s capacity to learn must be evaluated, and that learning capacity is the key to the person’s ability to generalise the material learned in one situation to others.

• If transfer of training does occur, then strategies to enhance this can be incorporated into other components of the treatment programme, such as those aimed at maintaining sitting balance, weight-bearing exercises or the functional use of the affected extremities (O’Sullivan & Schmitz,2007).

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Sensory integrative approach

• Ayres• Organization of sensation for use• Integration of basic sensory motor functions

(tactile, vestibular, proprioceptive) proceeds in a developmental sequence in the normal child.

• Production of an adaptive response facilitates sensory integration

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Neuro developmental approach

• To facilitate perception• E.g. Bilateral activity to unilateral neglect • Wt bearing activity to enhance perception

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Rehabilitative /compensatory (Functional) approach

Assumption• Adults with brain damage Will have difficulty in

generalizing and learning from dissimilar tasks• Direct repetitive practice of specific functional skills that are

impaired is an efficient approach.• The environment in which practice is taking place should

be Similar to home environment so that less generalizing is required.

• Components of functional approach:1) Compensation and 2) Adaptation

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• Compensation:• Changes that need to made in the patient’s approach to takes• Adaptation:• Alteration that to be made in the environment in order to facilitate

relearning of skills• Compensation:• Patient should be made aware of the deficiencies (cognitive

awareness).• Environmental scanning• Eg. Visual neglect- make the patient turn the head to see the other

½ to compensate for his disability.• Adaptation:• Make alteration in the patient strategy and environment.• Eg. Hemi neglect – a red tape stuck on his affected side shoe

during gait training.

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• Guideline while teaching compensatory approach

• 1)Use simple direction• 2)Establish and carry out a routine• 3)Do each activity in consistent manner • 4)Employ repetition• Limitation• Method learned in one task are not typically

generalized to the performance of another task.

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Cognitive rehabilitation and QUADRAPHONIC APPROACH

Addresses- dysfunction of memory ,language Disorder and perception

• also include information processing , awareness , judgment and decision making

• cognitive remediation approach helps in transfer of training

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Perception training:

• Can divide in 2 part 1)Remedial approach :• S.I. , Transfer of training ,Cognitive

rehabilitation2)adaptive/compensatory aapproach • functional approach

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Assumption underlying remedial and adaptive approach

Compensatory approach Remedial approach

1. Adult brain is less plastic2. Intact behavior can be used for

compensating impaired ones.3. Provides training of ADL functions.4. Adults with brain injury have

difficulty in generalizing learning.5. Adaptation and compensation will

lead to improved functional performance

1. Adult brain can repair and reorganize after injury.

2. Repair and reorganization is influenced by environmental conditions.

3. Cognitive perceptional and sensorimotor motor behaviors can promote brain recovery and reorganization.

4. Can generalize gained skills through remedial approach.

5. Cognitive and perceptual remediation will lead to improved functional performance

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Types of cognitive and perceptual deficit

Cognition: 1) Attention Sustained- divided Selective- alternating2) Memory

Immediate Short term Long term

Higher order cognition : 3) Executive functions Volition, planning Purposive action Effective performance

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Perception: 4) Body scheme/body imageUnilateral neglect ,R/L discrimination Anasognosia, finger agnosia , Somatognosia

5) Spatial relation disorders:Figure-ground discrimination ,Form constancySpatial relations ,Topographic disorientationDepth and distance perception, vertical

disorientation, position in space 6) Agnosia 7)Apraxia Visual IdeomotorAuditory ideationalTactile bucofacial

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Attention

Ability to select and attend to a specific stimulus while simultaneously suppressing extraneous stimulus .

Feature • Difficulty in processing and assimilating new

information• low arousal level eg CVA

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Yerkes Dodson law

• INVERTED U HYPOTHESIS• The proposition that optimal task

performance occurs at an intermediate level of arousal, with relatively poorer performance at both

lower and higher arousal levels, leading to an inverted U relation between arousal and performance

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Classification

TYPE STIMULI RESPONSE SUSTAINED CONTINIOUS SINGLE CONSISTANT

FOCOUSED OR SELECTIVE

MULTIPLE FOCOUS OR CONSISTANT TO ONE

ALTERNATING MULTIPLE MOVE FLEXIBELLY DEPENDS UPON TASK DEMAND

DIVIDED MULTIPLE SIMULTANEOUSLY TO 2 OR MORE WHEN ALL STIMULI ARE RELEVANT

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• LESSION AREA: RAS,limbic and frontal region underlie drive and affective component of concentration, various sensory system that deliver and code relevant sensory information

• Testing :serial seven test Spelling a five letter word from backward • Chessington Occupational Therapy Neurological

Assessment Battery (COTNAB)• Lowenstein Occupational Therapy Cognitive

Assessment(LOTCA)• Paced auditory serial addition test • Trial making test

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LOTCA• It includes 25 subtests in 6 area • Orientation (2 subtests): orientation to place and time.• Visual Perception (4 subtests): ability to identify pictures of everyday objects,

objects photographed from unusual angles, distinguish between overlapping figures, and recognize spatial relations between objects.

• Spatial Perception (3 subtests): tifferentiate between right and left to determine spatial relationships between objects and self.

• Motor Praxis (3 subtests): Asesses the individual's ability to imitate motor actions, use objects and perform symbolic actions.

• Visuomotor Organization (7 subtests): Assesses the individual's ability to copy geometric figures, reproduce a 2D model, copy a coloured block design and a plain block design, reproduce a puzzle and complete a pegboard task, and draw a clock.

• Thinking Operations (7 subtests): Assesses the individual's ability to complete tasks including sorting, categorization, and picture and geometric sequences

• scoring is on an ordinal scale of 1-4 (1-severe deficit and 4-average performance ) , except for orientation scores that range from 1-8.

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COTNAB• 12 test in total • Use for above 16 years age • Visual Perception• Overlapping figures Hidden figures Sequencing• Constructional Ability• 2D construction 3D construction Block printing• Sensory-Motor Ability• Stereognosis & Tactile Dexterity Co-ordination

Discrimination• Ability to follow Instructions• Written instructions Visual instructions Spoken• Each test is scored for Ability and Time which are combined to give a

measure of Overall Performance and a Functional Profile summary.

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Paced auditory serial addition test

• Every 3 sec 1 single letter is given for 3 min • Total score is 60

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Trial making testConsist of 25 circles distributed over a sheet of paper. In Part A, the circles are

numbered 1 – 25, and the patient should draw lines to connect the numbers in ascending order.

• In Part B, the circles include both numbers (1 – 13) and letters (A – L); as in Part A, the patient draws lines to connect the circles in an ascending pattern, but with the added task of alternating between the numbers and letters (i.e., 1-A-2-B-3-C, etc

• without lifting the pen or pencil from the paper time taken by the patient as he or she connects the trial should note .If the patient makes an error, point out immediately and allow the patient to correct it.

• It is unnecessary to continue the test if the patient has not completed both parts after five minutes.

Average Deficient rule of thumb• Trail A 29 seconds > 78 seconds Most in 90 seconds• Trail B 75 seconds > 273 second Most in 3 minutes

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Treatment

• Aim: increase attention to appropriate stimuli and disregard inappropriate stimuli.

• Remedial approach: visual scanning • lt hemiplegic should encourage to use verbalization to

improve visualization and vice versa for rt .• Setting time and speed limit, amplification of critical

stimuli and make crucial stimuli salient (noticeable) • Training in close to open environment .• Compensatory: avoid distraction due to external

stimuli

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Memory

• Mental process that allows individual to store experiences and perception for recall at a latter time .

• Information processing model

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• There are three stages that must take place for memory to occur ENCODING,STORAGE ,RECALL

• Most memory problems are due to lack of attention, so the information never gets processed in a meaningful way (encoded) and never makes it to storage. Making a conscious decision to pay attention is the first important step toward improving memory skills. Then simple techniques can help to process information so it stands a better chance of making it to storage for retrieval.

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Immediate recall and short term memory

• Immediate memory is the ability to remember a small amount of information over a few seconds. what you can repeat immediately after perceiving it

• Short term memory that is capable of storing material for a brief period of time Short-term memory (or "primary" or "active memory") is the capacity for holding a small amount of information in mind in an active, readily available state for a short period of time. In contrast, long term memory indefinitely stores a seemingly unlimited amount of information.

• Short-term memory should be distinguished from working memory, which refers to structures and processes used for temporarily storing and manipulating information

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• Remedial approach: improve attention skill • Organizing material to be remembered and

making logical association.• Compensatory:memmory log • Environmental prompt such as wall calendar

beeper

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Long term memory

• Structure involved: hippocampus and amygdela(limbic memory structure)

• Testing: recall of personal historical event • RBMT• Question the family about premorbid

memory.

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Types of Memory - Declarative

Explicit - person’s knowledge base, conscious awareness, “learning that”

– Working - ability to hold information while working with it (eg. math calculations)

– Semantic - general knowledge of concepts, rules, principles & meanings (eg, knowing that a cat is an animal)

– Episodic - remember specific personally experienced events (eg, holiday taken last year)

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Non-Declarative

Implicit - without conscious awareness, “learning how”

Procedural - skills becomes automatic through practice (eg, riding a bike)

Priming - cues prompt accurate recall without awareness (eg, name starting with M)

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Prospective

• Remembering to do something in the future or carry out intentions

• Remembering to remember• Most practical aspect of everyday memory Eg. pick children up after school

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Why Should PTs Assess Memory?

• Memory impairments can cause great difficulty in performance of everyday tasks

• Memory impairments can be a major barrier to rehabilitation - individual is unable to learn or carry over the techniques taught in the therapy sessions

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Commonly Used Assessments

• Contextual Memory Test, 1993

• Rivermead Behavioral Memory Test, 1985

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Contextual Memory Test (CMT)

• Purpose/Focus - created to assess awareness of memory capacity (metamemory), strategy use, and recall

• Population - adults 18 + years, tested on a wide variety of diagnoses

• Approach – structured interview & assessment• Unique Feature - tests a person’s insight into the

knowledge of their memory limitations

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CMT – Process Part 1

Step #1 - Administer memory questionnaire (#1-9)

Step #2 - Present picture card non-contextual method

Step #3 - Immediate recall of pictures

Step #4 - Administer memory questionnaire (#10-20)

Step #5 - Delayed recall of pictures (after 15-20 min)

Step #6 - Repeat administration of 2nd part of memory questionnaire

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CMT – Process Part 2• Perform with people who fall below norms in Part I,

2 to 36 hours after

• Steps #1-6 same as Part I, however, present alternate picture card, context method (Eg. as you study objects, think of what you do in the morning)

• If during step #5 (delayed recall) person has difficulty recalling items, may use retrieval cues.– Recall cuing first (Eg. What do you eat with?)– If poor performance with recall, use recognition cards (Eg.

Do you remember seeing this on the Picture Card?)

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Scoring

• Various scores with norms– Immediate Recall (IR)– Delayed Recall (DR)– Total of IR + DR– Strategy score– Predicted score– Discrepancy score

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Analysis of TestInformation Processing:Short term - Immediate recallLong term – Delayed recall (recognition) Types of Memory: Episodic (medial temporal lobe) – Picture Card event Semantic (neo-cortex, non frontal)- General knowledge of

objects on Picture Card Memory Processes: Encoding – visual, intentional Retrieval – free recall, (cued recall)

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• Reliability – Test-retest correlations for immediate and delayed recall .85-.94.

(Mackler, MMY)– Test-retest correlations for person’s with BI .85-.95 (Josman et al.,

2000)• Validity

– Concurrent (correlated with RBMT) - upper .70s to mid .80s (Raphael, MMY)

– Concurrent (correlated with RBMT) is .80-.84 (Josman et al., 2000)

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Rivermead Behavioral Memory Test (RBMT)

• Purpose/Focus – developed to detect impairment of everyday memory functioning & monitor change throughout treatment

• Population - adults 16 - 69 years, tested on a wide variety of diagnoses

• Approach – structured assessment• Unique Feature – attempts to simulate demands

placed on memory by normal, everyday life• Versions – 2nd edition, elderly, extended, children

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RBMT - Process1. First & Second Name2. Hidden Belonging3. Appointment4. Story - immediate & delayed5. Pictures - delayed6. Route - immediate & delayed7. Message - immediate & delayed8. Faces - delayed9. Orientation & Date• Each subtest has its own section & instructions on score

sheet• 2 scores produced

– Screening score (separate per subtest)– Standardized profile score (whole test

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Memory training strategy• Association • Visualization • Repetition and rehearsal

Repeat new information to yourself several times, spacing out these repetitions over time. you need to.

• Compensation Confucius, who said, “The weakest ink is stronger than the best memory.” In other words, if you want to remember something, write it down.

• Having a good system for recording information is critical. This usually includes a calendar for appointments and a memory notebook.

• reference material such as name, phone numbers, medications• list of things to do, including a space to mark off when completed• an alarm clock or oven timer, or using a small hand-held tape recorder for

pertinent information.

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Executive function

• Include the capacity to plan ,manipulate information ,initiate and terminate activity ,recognize error ,problem solve and think abstractly.

• Executive function consist of those capacities that enable a person to engage successfully in independent puposive,self serving behavior .

• Set of processes that underlie flexible goal-directed behaviour (e.g. planning, inhibitory control, attentional flexibility,working memory), Bianchi (1922)

• High-order control processes

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components of Executive abilities

• Lezak 1995 - Suggests there are 4 components of Executive function:– Volition– Planning– Purposeful behaviour– Effective performance

• Volitional – realization of one’s goals (what he wants do?)• Planning- weighing alternative ans making choices .- Organization of steps and elements.• Purposive action – ability to start, stop, switch to another

component, maintain sequences of action in an orderly manner.• Effective performance:• Quality control • Self correction

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• Stuss 1987 - Identifies a number of associated skills necessary for goal-directed behaviour– Ability to shift from one concept to another– Ability to modify behaviour in light of new info– Ability to synthesise & integrate isolated details into coherent

whole– Ability to manage multiple sources of information– Ability to make use of relevant acquired knowledge

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Anderson et al. (2001) propose 3 separable but unified components of EF:

1.) Attentional control: selective attention and sustained attention

2.) Cognitive flexibility: working memory, attentional shift, self-monitoring, and conceptual transfer

3.) Goal setting: initiating, planning and organisation, generating and implementing strategies for problem solving, and strategic behaviour

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What is Executive Dysfunction (dysexecutive syndrome)?

1.) Behavioural features - Poor self-control, impulsivity, erratic careless responses, poor initiation of speech, inflexibility (Lezak, 1995)

2.) Cognitive features – People with Executive Dysfunction exhibit poor performance on tasks which require one to use Executive Abilities– Tasks developed for use with adult participants

with brain injuries– Large range of tasks tapping into various aspects

of EF

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What is executive dysfunction?

• 3). Biological features• The “Frontal Metaphor”• Association noted between tasks which

involve EF processes and damage to the pre-frontal cortex

• Neuropsychologists may say an individual’s symptoms “look frontal”, without knowing the nature of the brain damage

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• Assessment:• hemi – imulsivensess,• poor judgment • poor planning ability• lack of foresight

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Rey-Osterrieth ComplexFigure

• examinees are asked to reproduce a complicated line drawing, first by copying and then from memory. the test therefore permits the evaluation of different functions, such as visuospatial abilities, memory, attention, planning, and working memory (executive functions). First proposed by Swiss psychologist André Rey in 1941 and further standardized by Paul-Alexandre Osterriethin 1944, it is frequently used to further elucidate any secondary effect of brain injury in neurological patients, to test for the presence of dementia , or to study the degree of cognitive development in children

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Stroop Task

• Read colour words

• Either congruous or incongruous

• Take longer if incongruous

• Involves selective attention & inhibition

RED

BLUE

GREEN

YELLOW

RED

BLUE

GREEN

YELLOW

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Tower of Hanoi

• Move all hoops from left peg to right peg without putting larger hoop on top of smaller

• Involves attentional shifting, planning, inhibition

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Body scheme/Body image disorder

• Body image: visual and mental image about one’ body – that includes feeling about one’s especially in relation to health and disease. Perception of body size.

• Body scheme: PERCEPTION OF own body parts, Postural model of body, including relationship of body parts to each other and relationship of body parts to environment .

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Unilateral neglect: • Inability to register and integrate stimuli and perceptions from one

side of the body (BODY NEGLECT) or the environment (spatial neglect )which is not due to sensory loss ( intact vision)

• Many terms are used unilateral spatial neglect, hemi-inattention, visual neglect and hemi spatial neglect

• does not try to compensate by turning head may even deny that side belongs to him ,avoids crossing the midline visually or during motor activity , when dressing forgets to put on (L) sleeve forgets to shave (L) ½ of his face ,neglect to eat from (L) ½ of his plate, reads newspaper till midline.

• Lesion area :inferior posterior region of right parital lobe • Assessment: • BIT- Behavioral Inattention test • Copy the drawing ,Observe performance Dressing ,eating ,reading,

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Behavioral inattention test

• The BIT, initially called as Rivermead Behavioural Inattention Test• The BIT is divided into two subtests: Conventional and

Behavioural. The BIT Conventional subtest (BITC) consists of 6 items: line crossing, letter cancelation, star cancellation, figure and shape copying, line bisection, and representational drawing. The BIT Behavioural subtest (BITB) consists of 9 items: pre-scanning, phone dialling, menu reading, article reading, telling and setting the time, coin sorting, address and sentence copying, map navigation, and card sorting.

• Cut-offs scores for the BIT, BITC, and BITB are respectively 196 out of 227, 67 out of 81 and 129 out of 146 (Halligan et al., 1991; Menon & Korner-Bitensky, 2004).

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Management • Remedial : by activation of motor circuit of same hemisphere • Use different shapes and size of objects to stimulate (R) hemisphere

activity. Avoid calculation to prevent (L) hemisphere ,verbal instruction to (L) motor activities (clenching fist)

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• Adaptive:Instructions from unaffected side Placing mirror while dressing Sonsorimotor approach on (L) side: ice, brush.Move the television from midline to affected side

• Cognitive compensation:-taught to be aware of the deficit -visual scanning

• Functional approach:-Repeat functional task-break sown into small components

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Evidence based approach

• Visual Scanning :• individuals with neglect do not visually scan their whole

environnent (Weinberg et al. 1977)• paying no attention to their left-sided space (Ladavas et

al. 1994). Cicerone et al. (2000) noted that the research literature concerning remediation of visuospatial deficits encompassed two basic approaches. One group of studies addressed the remediation of basic abilities and behaviour such as visual scanning or visual perception while the second focussed on the remediation of functional or constructional activities requiring spatial ability.

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Activation Strategies Activation strategies are intended to increase orientation and attention to the neglected hemi space. A stimulus, either a motor stimulus or externally applied sensory stimulus, to the affected side is thought to “activate” the right hemisphere. The mechanism by which this might improve neglect is still under debate. The activation may be a general activation of the right hémisphère (Robertson et al. 1994), which improves attention control in the neglected space (Kinsbourne 1987 cited in Bailey et al. 2002). Others postulate a personal space system that, when activated, improves the representation of the left-sided personal space (Robertson 1999 cited in Pierce & Buxbaum 2002). Activation strategies include limb activation as well as the application of a sensory stimulus.

1. Limb Activation2. Sensory Stimulation Interventions.3. Feedback Strategies :Feedback strategies are intended to improve

awareness of and attention to the neglected space (Pierce & Buxbaum 2002). Typical methods of feedback used include auditory and visual.

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• Prism Treatment As noted by Rossi et al. (1990) Prisms affect spatial representation by causing an optical deviation of the visual field to either the left or the right other optical aids have been used to achieve a similar effect including wideangle lenses (Drasdo 1976, Weiss 1969), mirrors attached to the spectacle frame (Nerenberg 1980, Nooney 1986, Duszynski 1955) and closed circuit TV monitor systems(Turner 1976).

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Eye-Patching and Hemispatial Glasses Beis et al. (1999) eye patches can be used to alter the processing of visual information by affecting the information processing structures of the central nervous system.” Shulman (1984) noted that in healthy subjects, eye patches should increase eye movements towards the contralateral space. Thus, eye patching of the eye ipsilateral to the lesion causes patients to look toward contralateral space by either moving their eye or by movement of the head.

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• Caloric/Vestibular Stimulation: when cold water is funnelled into the external ear canal, the vestibular-ocular reflex induces the slow phase of nystagmus toward the stimulated ear (Pierce & Buxbaum 2002). If warm water is used, this slow phase is directed away from the stimulation.

• Vestibular Galvanic Stimulation Caloric stimulation, while producing some transient, beneficial effect on neglect, has been criticised for being relatively impractical for use in applications outside of research (Rorsman et al. 1999). Rorsman et al. (1999) propose that stimulation of the vestibular system is possible without the discomfort and inconvenience associated with irrigation. Galvanic stimulation involves electrical stimulation of the vestibular nerves at a very low level (Rorsman et al. 1999).

• Optokinetic Stimulation Optokinetic stimulation functions in a fashion similar to vestibular stimulation in that it is based on the induction of nystagmus by exposure to a stimulus. Optokinetic stimulation uses a visual stimulus moving linearly from right to left (Pierce & Buxbaum 2002).

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• Trunk Rotation Therapy the orientation of the trunk midline in space functions as the dividing line between our personal representation of left versus right space and acts as an anchor for the calculation of body position (Karnath et al. 1991). Karnath et al. (1993) demonstrated that turning only the trunk of the patient to the left such that both right and left stimuli were projected to the right side of the trunk could compensate for deficits in reaction times to stimuli in the left visual field

• Neck Muscle VibrationKarnath et al. (1993) demonstrated that the detection and identification of stimuli in the left visual field in patients with neglect could be improved by trunk rotation, resulting in the lengthening of left posterior neck muscles, or by somatosensory stimulation applied to the left posterior neck muscles in the form of neck muscle vibration.

Transcutaneous Electrical Nerve Stimulation (TENS) Transcutaneous electrical nerve stimulation (TENS) is an alternate form of somatosensory stimulation thought to be capable of reducing neglect in a fashion somewhat similar to that of neck muscle vibration (Vallar et al. 1995).

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• Virtual reality• With virtual reality technology, the user is immersed in a

rich, multimodal, 3D world. Computer-generated virtual reality environments are interactive and realistic, with parameters and applications within the environment that are easily controlled. Application of virtual reality techniques does lead to improvements in performance for individuals with neglect on standard measures of neglect and on ‘real-life’ virtual tasks A recent review by Tsirlin and colleagues provides a thorough discussion of the potential uses of virtual reality in neglect assessment and intervention in the hope of spurring more research in this area.

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Anosognosia• A lack of awareness of impairment, not knowing that a deficit or illness

exists, in memory or other function• The impairment may be in memory, thinking skills, emotion, or

movement.• lack of awareness or denial of a paretic extremity as belonging to the

person. • disowning paralyzed limbs patient maintains that nothing is wrong with

him. it has been considered a temporary condition• common in the acute and post-acute phases. The presence of anosognosia

in a chronic phase (i.e. lasting more than few weeks) is a rare occurrence,• Lesion is usually located in non dominant (R) parietal lobe• Assessment :• By faking to patient.• It is difficult to compensate for anosognosia safety is main concern• In some patients anosognosia disappeared immediately following caloric

vestibular stimulation(Gianna Cocchini 2002

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• However, very recently, Fotopoulou and colleagues provided preliminary evidence that self-observation of motor behaviour from the third-person perspective may lead to permanent recovery

• People with anosognosia will often confabulate. Confabulation is making up an answer or responding with remarks that link pieces of information, time, places, and people that do not belong together. Sometimes people will combine memories from different events and insist that the event unfolded that way.

• They may describe an event as recent but it actually happened decades ago with different people. Sometimes they mix information from the newspaper or television with a personal event.

• A confabulation is not a lie.

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Somatognosia• Impairment of body scheme ,lack of awareness of body

structure and relationship of body parts to oneself or to other

• Have difficulty to follow verbal instructions • Have difficulty in imitating movement • Lesion: dominant parietal lobe (L)• Assessment- point to the body parts named by the examiner,

imitate movement ,required to answer question about relationship of body parts .

• Remedial: sensoriomotor approach, using different sensory input

• Verbally identify body parts or point the part on the picture

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Rt -Lt discrimination

Inability to identify (R) and (L) sides of one’s own body Or of others

• c/f unable to respond to verbal command contain rt /lt • Unable to imitate movement lesion: parital lobe (any side)• Assessment : ask the patient to point to body parts

first without using rt and lt latter with(R) ear, (L) foot.• Compensatory:• avoid words (R) & (L) instead command should be arm

with the watch• Adaptive environment: right side of all objects should

be marked with red tape e.g.. Shoes, clothing.

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Finger agnosia:

• Inability to identify finger of one’s one hands or of the examiners

• Feature: difficult on naming finger on command ,identify which finger was touched and difficult to mimic finger movement

• Lesion: parietal lobe• Assessment: sauguet’s test :touch the finger named

by therapist on self ,on therapist and in the picture total 10 command in each.

• Remedial :Sensori motor approach

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Spatial relations disorder

• Inability to perceive relationship between the self and 2 or more objects. (inability of space perception)

• Lesion: (R) parietal lobe- (L) hemiplegiaA)Figure ground discrimination:• -inability to distinguish a figure from its background • FEATURE :can not locate items in a drawer, locate button

on a shirt, words on a paper• Lesion area: parito occipital region of rt • Assessment:Ayres figure –ground test :require subject to

distinguish 3 subject from 6 embedded item

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Functional assessment :Ask the patient to find a white towel placed on a white paper

• Pick a spoon from unsorted array of eating utensils • Rule out poor eye sight, hemianopsia, visual agnosia, poor

comprehension• Remedial: arrange object in a simple array that is 3 object and

ask to identify latter increase more • compensation: awareness of the deficit• -make use of other sense –touch• adaptation: simplification of environment placing red tape• Make the edge of the stairs with brightly colored tapes.• Functional approach:• Repeated practice of a task• Transfer of training

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Form discrimination:

• Inability to perceive differences between forms and shapes. ( key, cup, pin)

• Confuse a pen with a tooth brush.• Lesion: non dominant parito-temporo-occipital association

areas• Testing : arrange different shape and forms of matarial

together and ask to identify 1.• Remedial: practice by describing ,demonstrating and

identifying use of similarly sized and shaped object .• Compensatory :labeled object if pts can read ,use of vision,

touch self verbalization

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Position in space

• Inability to perceive and interpret spatial concepts up, down, behind

• Area ;non dominant parital• Testing :give 2 object and ask to place1 in

different location in relation to other like pen above head

• Remedial ;3-4 identical object placed in some orientation and in another location

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Topographic disorientation

• Unable to understand and remember relationship between one location to another.

• Going from one room to another.• Difficult to go out of the house without an attendant• Lession :right retrosplenial cortex • Remedial :practising going from one place to another

on verbal command ,initially simple route latter complicated

• Compensatory :marked frequently travelled route by coloured dots and gradually increase distance of mark.

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Depth and distance perception

• Inaccurate judgment of direction distance and depth .• Eg.Difficult navigation stairs.• Miss the chair when attempting to sit• continue pouring juice when glass is full.• Testing :ask to grasp object placing in different location,

ask to pour water in glass • Remedial :foot mark on the ground during gait

training ,ask for proper positioning of foot on instructed stairs

• Compensatory :manipulating object on environment

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Vertical disorientation

• Unable to perceive which is vertical.• Affects motor performance on posture and gait • Lession area ;nondominant parital• Assessment: therapist hold a cane vertically and

turn sideways ask pts to align on previous position• Remedial: line on a mirror align it with a line on

the shirt ,use of touch ,elevator instead of stairs

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Agnosia

• Inability to recognize or make sense of incoming information despite intact sensory capacities.

• dominant hemisphere lesion ( parietal)• Visual agnosia :Inability to recognize familiar objects despite

normal eye sight.(may recognize the same object by touching)• Eg. Recognize familiar faces (people) prosopagnosia• Familiar objects, colour agnosia. • Auditory agnosia: Different between ring school bell and

telephone • Tactile agnosia OR ASTEREGNOSIS: recognise form by

handelling them

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Treatment

• Remedial;practise on easy street environment (visual)

• If tactile :felling various common object with vision occluded

• Drilling patient on sound (auditory)• Compensatory :use of intact sensation

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Apraxia

• Impairment of voluntary skilled learned movement ,characterized by inability to perform purposeful movement not caused by weakness, deafferentiation (loss of sensory capacity), abnormality of tone or posture, abnormal movements, intellectual deterioration, poor comprehension, or uncooperativeness

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Ideomotor

• Inability to perform acts to verbal commands, even though they might be performed spontaneously, or when aroused emotionally

• Area:left dominant hemisphere • Test ;goodglass and coplan test :ask to do universally

known movement like chewing ,brushing ,blowing • Remedial:give very short command and slowly ,one

command at a time • Compensatory :use of picture of ADL on sequences

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Ideational

• And, “ideational apraxia” in which the patient identifies the wrong overall plan, despite preserving the elements. A common example is a patient who puts the match to their mouth to light with a cigarette in their hand. (large diffuse lesions and many question whether its not a severe form of ideomotor apraxia

• ideational apraxics failing on pantomiming but not imitation, and ideomotor apraxics on both

• consistent with the idea that ideomotor is just more severe. • Area:dominant parital lobe • Test and treatment :as ideomotor

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Buccofacial apraxia

• Difficult to perform purposeful movement with lips ,tongue ,cheeks on command

• Area frontal and central opercula ,anterior insula

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