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Neuropsychological
Assessment
Dr Youngsuk Kim, Highly Specialist Clinical Psychologist
Acknowledgement: Dr Jamie Macniven, Consultant Clinical Neuropsychologist of Nottingham University Hospital NHS Trust
Aims
– Modern neuropsychology
– Overview of differing approaches to clinical
neuropsychology assessment
– Components of neuropsychology assessment
– Diagnostic questions/process
– Patient effort
– Interpretation
– Common pitfalls
– Feedback
Modern Neuropsychology
• Assessment and rehabilitation of patients with
cognitive disorders
• Emphasis on the effects of large rather than small
projectile injuries
• Clinical vs academic neuropsychology
• Computer science theories/information processing
models
• Case-study approach rather than syndromes
Modern Neuropsychology
• Neurobiology of mood, cognition, insight,
consciousness
• Neuropsychiatry
• Inter-disciplinary work
• Ecological validity
Neuropsychological Models
• Many modern tests based upon models from
cognitive psychology
• Can explain deviation from ‘normal’ cognitive
processes
• Movement towards function-led rather than
construct-based tests
• Tension between construct-operation-function
Levels of Explanation
Level of
Explanation
Explanatory
Status
Construct
Operation
Function
Theoretical
Experimentally
detectable or
inferable
Directly observable
What is it?
Change in the
brain, “cognitive
system”, or “mind”
Change in the
individual
Change upon the
world
Example 1
“Theory of mind”
Take another’s
mental
perspective
E.g. empathic
behaviour
Example 2
“Working
memory”
Mental
E.g. Verbal rehearsal;
manipulation of
solving multi-stage
representations mental calculations
Purpose of Assessment
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Diagnosis
Management, care and planning
Evaluate effectiveness of treatment technique
Provide information for legal matter
Research
Assessment
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Clinical history
Symptom profile
Neurological test results
Imaging data
Neurological findings
Key Assessment Areas
• Must collect information on:
– Purpose of investigation – what does referrer want? Is this
neuropsychologically meaningful?
– Demographics – age, handedness, education/qualifications,
current/previous occupation, hobbies, cultural background
– Medical and psychiatric history
– Previous investigations – CT/MRI/EEG/ psychiatric opinions etc
– Results of previous neuropsychometry
– History of patient’s injury/disorder
– Factors that might affect testing – e.g. drug types and levels,
epileptic seizure activity, mood, motor/speech problems, effort
– Collateral history
– Context of assessment – e.g. medico-legal compensation
Approaches to Assessment
• Will depend on reason for referral, service
context, patient characteristics, ?clinician’s
orientation/ test preferences
• Test-battery vs hypothesis-led
• Quantitative vs qualitative
• Cognitive vs functional
• Diagnostic vs rehabilitative vs
?psychotherapeutic
• Impairment vs disability detection
Function-led Assessment
• To what extent does the simple, impoverished, and highly
artificial experimental task … have to do with the many
complex, rich, real-life experiences that people share?
(Kingstone et al, 2003)
• Attempts to develop function-led tests include the Multiple
Errands Test (Knight et al, 2002) and the Six Elements Test
(Manly et al, 2002)
Diagnostic questions
• Emergence of cognitive or behavioural problems without
a known aetiology
• Questions regarding nature or source of patient’s
condition are always questions of differential diagnosis
• Neuropsychological diagnostic criteria:
– Coarse screening – neurological impairment vs psychiatric or
emotional disturbance
– Fine discrimination between cog decline due to dementing
illness or growing tumour
– Even finer discrimination between specific focal lesion and
effects of lesion that may have encroached on adjacent part of
brain
• Diagnostic evaluations depend on syndrome analysis in
light of cognitive profile
Diagnostic process
• Personal and family history, nature and circumstances of
onset are vital clues
• Does cognitive profile fit a known pattern of brain
disease?
• Which cognitive functions are intact/ compromised?
• Successive elimination of hypotheses
– Formulate on basis of referral information/ history/ interview
– Test hypotheses by comparing what is known of condition to
what is expected in hypothesised condition
– Progressively refine general hypotheses
– Provide data and diagnostic formulations that contribute to the
diagnostic conclusions
– Do NOT make neurological diagnosis
Neuropsychology Answers to
Diagnostic Questions
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likely aetiology
functional implications
prognosis
rehab/treatment implications
Descriptive Questions
• Where diagnosis is established, referral
questions may call for behavioural descriptions
(e.g. vocational, educational, rehabilitation
planning)
• Capacity
• Monitoring disease progression/ treatment
effectiveness
• Baseline studies
Interview
• Focus on patient background with emphasis on
four aspects which provide context for
interpretation:
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Social history
Present life circumstances
Medical history and current medical status
Circumstances surrounding examination
• Sometimes only 2 or 3 of these available
• Must include some informant history and
medical records
Social History
“Historical data are the bricks, chronology is the mortar”
• Premorbid cognitive levels may be best estimated on
basis of educational and occupational history
• Socioeconomic status of patient and family may provide
important contextual info
• Cultural attitudes to testing process important
• Psychosexual history
• Spouse/partner’s health, social situation etc important in
formulating impact of condition
• Forensic history
• Family’s attitude to illness behaviour
• Employment performance
• Habits e.g. alcohol/nicotine etc
Present Life Circumstances
• Need to go beyond the usual level of
information-gathering
• Patient’s views and feelings regarding
occupation, income, family, spouse, leisure
activities, illness etc as important as the factual
information
• Quality of patient’s family life, sexual difficulties,
presence of conflict/ illness/ substance abuse in
family members etc can all adversely affect test
performance
Medical History and Current
Medical Status
• Medical information from referrer, medical notes,
psychiatric/neurology notes
• May be very significant omissions – e.g. diet,
sleep, visual/auditory deficits, alcohol
• Discrepancies between physician reports and
patient self-report
• Past and current medication – especially in
conditions such as epilepsy
Circumstances Surrounding the
Examination
• What is patient’s understanding of and attitude
to the assessment?
• Are there internal or external factors that might
influence patient’s motivation or effort?
• Financial/employment/family implications of
performance on testing?
• What does the patient believe they will gain or
lose from the results of the tests?
Examples of Neuropsychology Tests/Batteries
1.
Brief screening
includes Abbreviated Mental Test, Mini-Mental State Exam,
Addenbrooke’s Cognitive Evaluation- revised, Visual Object and
Space Perception Battery
2.
Intellectual assessment
includes premorbid intelligence and current intellectual functioning
using Wechsler Abbreviated Scale of Intelligence, Wechsler Adult
Intelligence Scale-III
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Memory
includes Rivermead Behavioural Memory Test, Wechsler Memory
Scale
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Language
includes WAIS-III verbal subtests, Graded Naming Test, Verbal
Fluency
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Executive functioning
includes Wisconsin Card Sorting Test, Trail Making Test, Behavioural
Assessment of the Dysexecutive Syndrome
Effort
• See National Academy of Neuropsychology statement in USA:
– “Assessment of response validity as a component of a medically
necessary evaluation is medically necessary”
Bush et al (2005) Archives of Clinical Neuropsychology 20, 419-426
– Differentiate between symptom validity, response bias, effort and
malingering
• Symptom validity: truthfulness of patient’s behavioural signs, self-reported
symptoms and performance on testing
• Response bias: cultural leading to exaggeration or denial of symptoms
without conscious or unconscious intent to deceive or personality factors
• Effort: emotional factors such as depression and catastrophic reaction can
affect cognitive efficiency; physical factors such as pain and/or fatigue can
interfere with patient giving ‘best effort’
• Malingering: the intentional production of false or exaggerated symptoms
motivated by external incentives
– “Although symptom validity tests are commonly referred to as
malingering tests, malingering is just one possible cause of invalid
performance.” (Ruff, 2006)
Qualitative Interpretation
• Manner in which tests are attempted
– e.g. approach to Block Design, recognition
that response is incorrect, catastrophic
reactions to failure etc
– Gratuitous responses: added adjectives,
adverbs, flights of fancy, spontaneously
introduced characters, objects or situations
reflect mood and betray preoccupations
Interpretation pitfalls
Overgeneralization
– e.g. test profile equates with known syndrome ‘same as arguing
that because a horse meets the test of being a large animal with
four legs then any newly encountered animal with four legs must
be a horse’
False negatives
– Absence of low scores will occur when brain damaged
individuals have not been given an appropriate examination
Confirmatory bias
– i.e. common tendency to ‘seek and value supportive evidence at
the expense of contrary evidence’ when the outcome is
presumably known
Interpretation pitfalls
Over & under-interpretation
– Single dramatic finding (which could be a simple mistake) may
be given much greater weight than a not-very-interesting history
that extends over years or base rate data
– On the other hand, a cluster of a few abnormal examination
findings that correspond with patient’s complaints and condition
might provide important evidence of a cerebral disorder, even
when most scores reflect intact functioning
Underutilisation of base rates
– Any sign that can occur with more than one condition as possibly
suggestive but never a diagnostic sign (e.g. slurred speech in
stroke, MS, acute alcoholism)
Feedback
• Report writing
– Clinical reports
– Patient versions?
– Medico-legal reports
• Face-to-face feedback to patient and family
• Working in community/medical/neurological/
neuropsychiatric teams: case formulation
approach
Key Sources
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Lezak et al (2004). Neuropsychological Assessment (4th Edition). Oxford:
Oxford University Press.
Evans, JJ (2003). Basic concepts and principles of neuropsychological
assessment. In PW Halligan et al, Handbook of Clinical Neuropsychology.
Oxford: Oxford University Press.
Goldstein, LH & McNeil, JE. (2004). What is the relevance of
neuropsychology for clinical psychology practice? In LH Goldstein and JE
McNeil (Eds.), Clinical Neuropsychology: A Practical Guide to Assessment
and Management for Clinicians. Chichester: Wiley.
Crawford, JR. (2004). Psychometric foundations of neuropsychological
assessment. In LH Goldstein and JE McNeil (Eds.), Clinical
Neuropsychology: A Practical Guide to Assessment and Management for
Clinicians. Chichester: Wiley.