Transcript Chapter 15

Chapter 15
Neuropsychological Assessment
Neuropsychological Assessment
• Neurology: the branch of medicine that
focuses on the nervous system and its
disorders
• Neuropsychology: the branch of
psychology that focuses on the relationship
between brain functioning and behavior
– Formerly a specialty area within clinical
psychology, has since emerged as a specialty in
its own right
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Neuropsychological Assessment
• Neuropsychological assessment: the
evaluation of brain and nervous system
functioning as it relates to behavior
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pediatric neuropsychology
geriatric neuropsychology
forensic neuropsychology
school neuropsychology
• Neurotology: a branch of medicine that
focuses on problems related to hearing,
balance, and facial nerves
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The Nervous System and
Behavior: Quick Overview
Nervous System is made up of:
1. Neurons: a nerve cell
2. Central nervous system: the brain and spinal cord
3. Peripheral nervous system: the neurons that convey
messages to and from the rest of the body
Note: Each of the cerebral hemispheres receives sensory
information from the opposite side of the brain, and also
controls motor responses on the opposite side of the
body (contralateral control)
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Neurological damage and
organicity
 Brain damage: a general reference to any physical or
functional impairment in the CNS that results in sensory,
motor, cognitive, emotional, or related deficit
 Organicity: organic brain damage
Note: There is a difference and these terms have been
mistakenly used interchangeably
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The Nervous System and
Behavior
How is neurological damage and organicity assessed?
Researchers utilize a multitude of tools and procedures:
MRI, fMRI, PET, CT imaging
Electrical or chemical stimulation
Surgical alteration
Laboratory testing
Field observation
Autopsies
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The Nervous System and
Behavior
How is neurological damage and organicity assessed?
 Lesion: a pathological alteration of tissue (e.g., that which could
result from injury or infection) – This change can be focal or
diffuse
 Lesions will manifest themselves in various behavioral deficits
 Neurological assessment can play a critical role in determining the
extent of behavioral impairment that has occurred or can be
expected to occur
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The Neuropsychological Evaluation
When is a neuropsychological evaluation indicated?
 In most cases a patient is referred to a psychologist for
screening of suspected neurological problems
 A battery of tests will be conducted (most likely including
an intelligence test, a personality test, and a perceptualmotor/memory test)
 If suspicious neurological signs are discovered the patient
will be referred for a more detailed evaluation
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The Neuropsychological Evaluation
When is a neuropsychological evaluation
indicated?
The signs suggesting a more thorough evaluation
are characterized by being “hard” or “soft”:
Hard sign: an indicator of definite neurological
deficit
e.g., cranial nerve damage as indicated by neuroimaging
Soft sign: an indicator that is merely suggestive of
neurological deficit
e.g., an apparent inability to accurately copy a stimulus
figure when attempting to draw it
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The Neuropsychological Evaluation
When is a neuropsychological evaluation
indicated?
– Neurologists may refer their patients to
neuropsychologists for further evaluation
– A neuropsychologist may be called upon to assess
the degree of a patient’s impairment in functioning
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The Neuropsychological Evaluation
General elements of a neuropsychological evaluation
Objective:The objective of a neuropsychological evaluation is
“to draw inferences about the structural and functional
characteristics of a person’s brain by evaluating an individual’s
behavior in defined stimulus-response situations” (Benton, 1994,
p. 1)
Method: How this is done involves a number of factors
including the nature of the referral question, the capabilities of
the patient, and the availability of records
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The Neuropsychological Evaluation
General elements of a neuropsychological
evaluation
Preparation includes ensuring the appropriate tools
of assessment are employed
Sometimes during the course of an evaluation, a
deficit becomes known and changes the course of
the assessment procedure
Common to all evaluations are patient history,
mental status exam, and administration of tests and
procedures
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The Neuropsychological Evaluation
General elements of a neuropsychological
evaluation
The neuropsychologist employs knowledge of
neuroanatomy, neurochemistry, and neurophysiology
to interpret findings and employ tests
Neuropsychologists must also be familiar with the
effects of various prescription medications
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The Neuropsychological Evaluation
Patient history
– Medical history of patient and immediate family
– Developmental milestones
– Psychosocial history (e.g., academic achievement,
intelligence, adjustment, personality, thought
processes, etc.)
– Character, severity, and progress of any history of
complaints involving disturbances in senses;
muscle tone, strength, and control; autonomic
functions; speech; etc.
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The Neuropsychological Evaluation
Patient history
– Can shed light on whether the problem is origin of
the problem as well as whether it is progressive
(likely to spread or worsen)
– May also reveal whether the patient’s presenting
problem is a result of malingering rather than some
deficit
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The Neuropsychological Evaluation
Interview
– Structured interviews and rating forms can act as
aids to neuropsychological screening and
evaluation
– Offers direction to further inquiry
– e.g., Mini-Mental State Exam (MMSE)
Neuropsychological mental status exam
– Administered for the purpose of evaluating
neuropsychological functioning
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The Neuropsychological Evaluation
Physical examination
– A physical exam varies widely as a function of the
expertise, competence, and confidence of the
examiner
– A physical exam looks at the examinee’s
appearance; scalp and skull; muscle tone, strength,
and size; reflexes; etc.
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The Neuropsychological Evaluation
Tests of general intellectual ability
– Such tests (especially Wechsler tests) are frequently used in
neuropsychological assessment
– The varied tasks on the Wechsler scales make the tests
particularly useful in neuropsychological screening
– Certain patterns of test responses indicate particular deficits
(pattern analysis)
– Several researchers are working to develop a definitive sign
of brain damage and as such have devised various ratios
and quotients based on pattern analysis
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The Neuropsychological Evaluation
• Tests to measure abstract ability
– One symptom associated with neuropsychological
deficit is an inability or decreased ability to think
abstractly
• One traditional measure of verbal abstraction ability is
the Wechsler Similarities Subtest
– Nonverbal tests of abstraction include any test that
requires the respondent to sort objects in some
logical way (e.g., “group together those that belong
together” and then follow-up questions)
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The Neuropsychological Evaluation
• Tests of executive function
– Executive function: organizing, planning,
cognitive flexibility, and inhibition of impulses
and related activities associated with the frontal
and prefrontal lobes of the brain
• e.g., Tower of Hanoi,
performance on mazes
• Clock-drawing test
(CDT): a test to quickly
screen for certain
executive functions
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The Neuropsychological Evaluation
• Tests of executive function
– Trail-making item: a task that is thought to tap
many abilities, including visuo-perceptual skills,
working memory, and the ability to switch
between tasks
– Field-of-search item: the testtaker must scan a
field of various stimuli to match a sample
• Useful in discovering visual scanning deficits
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The Neuropsychological Evaluation
• Tests of perceptual, motor, and perceptualmotor function
– Perceptual test: a general reference to any of
many instruments and procedures used to evaluate
varied aspects of sensory functioning
– Motor test: a general reference of any of many
instruments and procedures used to evaluate varied
aspects of one’s ability and mobility
– Perceptual-motor test: a general reference to any
of many instruments and procedures used to
evaluate the integration of perceptual and motor
abilities
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The Neuropsychological Evaluation
• Tests of perceptual, motor, and perceptualmotor function
– Jigsaw puzzles tap perceptual-motor ability
– Ishihara (1964) screens for color blindness
– Wepman Auditory Discrimination
Test
– Bruininks-Oseretsky Test of
Motor Proficiency
– Bender Visual-Motor Gestalt
Test
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The Neuropsychological Evaluation
• Tests of verbal functioning
– Verbal and writing fluency can be affected by
brain injury
• Aphasia: a loss of ability to express oneself or
understand spoken or written language because of some
neurological deficit
• Controlled Word Association Test has the examinee
recite as many words beginning with a particular letter
as they can
• Reitan-Indiana Aphasia Screening Test (AST) screens
for aphasia
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The Neuropsychological Evaluation
• Tests of memory
– Procedural memory: memory for skills (e.g.,
riding a bicycle)
– Declarative memory: memory of factual material
– Semantic memory: memory for facts
– Episodic memory: memory for facts in a
particular context or situation
– A widely used test of memory is the California
Verbal Learning Test-II (CVLT-II)
– Other tests of memory include Wechsler Memory
Scale (WMS-IV) and Seguin-Goddard Formboard
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The Neuropsychological Evaluation
• Neuropsychological test batteries
– A neuropsychologist typically administers a
battery of tests for clinical study
• Fixed battery
• Flexible battery
– A flexible battery of tests involves hand-picked
instruments relevant to the unique aspects of the
patient and presenting problem
• However, flexible test batteries risk overlapping with
respect to some functions tested, thus wasting time and
resources
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The Neuropsychological Evaluation
• Neuropsychological test batteries
– Fixed neuropsychological test batteries are designed
to comprehensively sample the patient’s
neuropsychological functioning
– Halstead-Reitan Neuropsychological Battery:
• The most widely used fixed neuropsychological test
battery
• Requires a highly-trained examiner and a full workday to
complete
• Scoring yields a number referred to as the Halstead
Impairment Index
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The Neuropsychological Evaluation
• Neuropsychological test batteries
– Another fixed neuropsychological battery is the
Luria-Nebraska Neuropsychological Battery
(LNNB)
• Contains scales to assess cognitive processes and
functions
• Analysis of scores may lead to judgments of whether
neuropsychological impairment exists and which area
of the brain is affected
• Takes approximately 1/3 of the time to administer as
the HR battery
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The Neuropsychological Evaluation
• Other tools of neuropsychological
assessment
– Neuropsychologists must be prepared to evaluate
persons who are vision-impaired, hearingimpaired, or otherwise disabled
– Perhaps the greatest advances in the field of
neuropsychology includes high technology and the
mutually-beneficial relationship between
psychologists and medical personnel
• MRI, fMRI, SPECT, CT, PET, EMG, EEG
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