Neuropsychological Assessment Flashcards
Basic aim of neuropsych assessment
- reliable and valid picture of the relationship between the brain and behaviour
- identification of cogniitive, emotional, motor and behavioural consequences of brain dysfunctions
central focus: assessment of cognitive dysfunctions
Reasons for neuropsych assessment
- is there evidence of organic brain dysfunction?
- diagnosis of brain pathology not always possible by neuroimaging, neurophysiological assessment, lab or physical markers
- cognitive impairment sometimes the only indicator of pathology
eg.
- mild cognitive impairment (MCI)
- dementia
- developmental disorders
what is nature and extent of cognitive impairment
eg
- is there memory deficit
- what aspect of memory are affected? (eg. short-term vs long-term memory, memory for verbal vs figural information, recall from memory vs recognition)
- how severe are the disturbances?
(eg. mild, moderate or severe)
what are the practical consequences of cognitive impairment?
- activities of daily living (eg dressing)
- driving capacity
- social functioning (social skills, social role, responsibilities)
- work/education
- leisure
in what way is an individual’s mood and behaviour affected by brain dysfunction?
- identification of mood disorders meaningful, since they
- need treatment
- may affect test performance (important for interpretation of test results)
- may be an additional burden for relatives
Does cognitive performance change over time?
- detection of the process of cognitive decline associated with progressive disorders (eg Parkinson’s disease, Alzheimer’s disease)
- recording the process of recovery from brain lesions (eg. traumatic brain injury, stroke)
- recording the effects of treatment (eg. neuro-rehabilitation, neurosurgery, pharmacological treatment)
Problem
Solution
Problem
Problem
Problem: Practice effects
Solution: Use of parallel versions of tests
Problem: no parallel versions available for most tests
Problem: and even if: Test idea known on retesting (no novelty effect (eg. in delayed recall tasks), reduced nervousness (eg. elderly on computerised tasks))
what are cognitive strengths and weaknesses of an individual regarding the rehabilitation process?
Example
Individual has intact visual memory and impaired verbal memory
rehabilitation efforts
supporting individual to develop compensatory strategies using the intact system
- providing feedback to patient and family
- improving patient self-awareness
approaches to assessment:
review of info from referrer
- begin of assessment
- great variability of available information
- only patient’s complaints (eg. difficulties remembering names or dates)
- Detailed clinical history, family history, brain images, neurological evaluation, data from former maps assessments
approaches to assessment:
Information from clinical and laboratory examinations
Can be related to neuropschological findings
- lesions localisation to cognitive functions (eg. MRI)
- cognitive decline with progressive diseases (eg. Alzheimer’s disease)
- Fluctuations in performance to epileptic seizures (eg. EEG)
approaches to assessment:
Clinical Neurological examination, what to do ?
Taking the patient’s history
- what are the complaints?
- what are complaints localised?
- when did complaints start?
- how did complaint start? (suddenly or gradually)?
- what course have complaints taken?
- which situations trigger or relieve complaints?
- what treatment has been tried?
approaches to assessment:
How many cranial nerves? and for what?
12 cranial nerves to relay motor functions, senses and reflexes of the head
- don’t need to learn the individual cranial nerves for the exam
- olfactory - smell
- optic - vision
- oculomotor nerve - eyelid and eyeball movement
- trochlear - innervates superior oblique turns eye downward and laterally
- trigeminal nerve- chewing face and mouth touch and pain
- abducens nerve - turns eye laterally
- facial nerve - controls most facial expressions secretion of tears and saliva taste
- vestibulocochlear nerve - hearing equilibrium sensation
- glossopharyngeal nerve - taste senses carotid blood pressure
- vagus nerve - senses aortic blood pressure slows heart rate stimulates digestive organs Tate
- spinal accessory nerve - controls trapezius and sternocleidomastoid - controls swallowing movement
- hypoglossal nerve - controls tongue movements
approaches to assessment:
motor functions
muscle power
paresis/paralysis = muscle weakness
plegia = complete loss of force
hemiparesis = weakness of one side of body
paraparesis = weakness of both legs
tetraparesis/quadriparesis = weakness of all four limbs
coordination (fine and gross motor movement)
finger-nose test (move index finger and touch nose)
Shin-heel-test (moving the heel too the opposite knee and along the shin)
posture and gait
(eg. patient stands straight or bent, secure or insecure)
approaches to assessment:
Romberg Test
Patient is asked to stand still with heels together
Patient is asked to remain still and close eyes
Some patients lose their balance
approaches to assessment:
Reflexes
biceps and triceps reflexes in arms, knee jerk, ankle jerk iiim legs
pathological reflexes indicate lesion in CNS
eg. Babinski reflex
occurs when great toe flex toward top of foot and other toes fan out when the sole of the foot has been firmly stroked
approaches to assessment:
cognition
brief mental state examination
full nosy examination provides significantly more detailed analysis of cognitive deficits
laboratory examinations
computerised tomography (CT)
transmission of X-rays through the head from different sides
strength measures by detectors on opposite side
weakening (absorption) during passage through head depends on density of tissue
spatial solution 2 mm
laboratory examinations
examples of computerised tomography
Hypodense areas are darker
indicates stroke, oedema, inflammation or certain brain tumours
hyper dense areas are lighter
indicates fresh bleeding, calcification or other brain tumours
laboratory examinations
size of ventricles
increase in size indicates hydrocephalus or brain atrophy
decrease in size indicates brain oedema (swelling of brain)
laboratory examinations
Magnetic resonance imaging (MRI)
Hydrogen protons (H+) in brain tissue constantly rotate (spin)
powerful magnetic field forces all protons into a single direction
direction briefly diverted by short electromagnetic impulses
emission of high-frequency radiation (echo), when returning to previous state
echo can be measured by MRI
characteristic of each proton’s echo is influenced by surrounding brain tissue
consequently generation of high-resolution pictures of the brain
spatial solution 1mm
functional MRI (fMRI) not used in routine clinical practice
laboratory examinations
single-photon emission computer tomography (SPECT) and positron emission tomography (PET)
use of radioactive substances (tracers) in both (injected or inhaled)
uptake preferentially in most active brain areas
therefore images of blood flow and activity of different brain areas
no detailed anatomical pictures (in contrast to CT, MRI)
spatial resolution 1-2 cm in SPECT and 0.5-1 cm in PET
both rarely used in clinical practice
both (SPECT, PET) allow study of receptor binding
eg.
dopamine receptors of patients with Parkinson’s disease
decrease in dopamine as the disease progresses (in putamen)
laboratory examinations
angiography (or arteriography)
conventional x-ray examination after injection of iodine-containing contrast substance
leads to visualisation of arteries and veins
laboratory examinations
showing
stenosis (narrowing) of an artery
blockade of an artery
aneurysms (bulging of artery by a weakness of artery wall)
Arteriovenous malformation or angioma (AVM, a tangle of pathological vessels)
pathological vessels in a brain tumour
laboratory examinations
electroencephalography (EEG)
Hans Berger recorded the first human EEG in 1924
he noted rhythms in the electric activity - brain waves
the first one he noticed he called alpha waves
laboratory examinations
electroencephalography (EEG) how it works
neurons generate action potentials that bread across axons and dendrite
multitude of action potentials of cortisol neutrons adds up to electrical field potentials
measurement of electric activity of cerebral cortex
most important use
searching for signs of epileptic activity
EEG abnormality also in other diseases, such as
eg.
degenerative diseases such as Alzheimer’s disease
general slowing (indication of)
brain tumours
focal changes of rhythm or shape of EEG waves
laboratory examinations
evoked potentials
electric responses recorded from scalp surface as a response to an external stimulus
recording of reaction of primary cortisol areas to external stimulation
provide information about the functioning of sensory or motor pathways
visual evoked responses (VER)
flickering checkerboard
brainstem auditory evoked responses (BAER)
somatosensory evoked responses (SSER)
motor-evoked responses (MEP)
transcranial magnetic stimulation
measurement of evoked response requires application of hundreds of consecutive stimuli
latencies, amplitudes and shapes of waves are altered when items are dysfunctional
laboratory examinations
Event-related potentials (ERPs)
recording of reaction of secondary cortisol areas to external stimulation
ERPs considered to represent cognitive processes (eg. focussing of attention)
most commonly used ERP’s
P300 (positive potential approx 300 ms after stimulus)
N400 (negative potential approx 400 ms after stimulus)
laboratory examinations
Doppler ultrasound
detection of stenosis (narrowing) of an artery leading blood to the brain (internal carotid or vertebral artery)
blood supply to a part of the brain compromised
probe is pressed on skin above one of these arteries
probe emits ultrasound
ultrasound bounces back from blood cells
same probe records returning signal
character of returning signal gives information about blood flow
increase in bloodstream as an indication of a stenosis
laboratory examinations cerebrospinal fluid (CSF)
collection by lumbar puncture
supports in diagnosing
hydrocephalus
increased CSF pressure
subarachnoid haemorrhage
CSF gained with blood
Inflammation
increased amount of protein and leukocytes in CSF
Brain tumours
Pathological tumour cells in CSF
Clinical Interview
interview of patient and relative (if necessary separately)
tactful and systematic questions to determine patient’s perspective on problems, history, disturbances and impact of daily living
discrepancies between patient and relative are worth noting
inaccurate reports of patients because of memory disturbances
unawareness of or indifference to the existence of disturbances (ansognosia, anosodiaphoria)
overestimation of disturbances (less frequent)
Clinical Interview
brief informal assessment of
temporal spatial orientation
understanding verbal instructions
language functions
formulation of adequate sentences
storing and retrieval of new information
autobiographical information
main biographical steps and milestones in personal and familial life
eg recent holidays, school periods, academic/professional training, wedding, children’s birth, jobs, retirement)
Clinical Interview
Questionnaires and symptom checklists
prompting patients and relatives to report problems that may otherwise be forgotten or unstated
eg assessment of
behavioural disturbance
impact of cognitive deficits on daily activities
increase of burden for relatives
standardised tests
main tool in neuropsychological assessment
designed to assess specific cognitive functions
accepted as a euro-diagnostic tool (independent from EEG, neuroimaging, etc)
crucial difference to other methods (eg. observation, interview)
no other profession trained to apply tests (eg. physicians, physiologists, physiotherapist)
neuropsychological testing expertise –> unique service –> differentiating –> neuropsychologist from other psychologists and non-psychologists
ability to design, apply and interpret neuropsychological tests –> defining characteristic of clinical neuropsychology
administration of tests in standardised fashion (as outlined in a test manual)
normative data
like a control group, stratified for factors such as age, gender, etc
allows comparison between individual test score and average score of population also considering variability in normal population
allows quantification of deficit (eg percentiles)
certain groups are often not well represented in normative samples of tests (eg. elderly people, people with learning disorder)
standardised tests
Graph and classification off ability levels
refer to powerpoint
classification of ability levels
classification
very superior z score is 2 and above percent included 2.2 lower limit of percentile range 98
superior 1.3 to 2 percent included 6.7 lower limit of percentile range 91
high average 0.6 to 1.3 percent included 16.1 lower limit of percentile range 75
borderline z score -1.3 to -2 percent included 6.7 lower limit of percentile range 2
retarded z score -2.0 and below percent included 2.2 lower limit of percentile range _
standardised tests
1. comprehensive or big battery approach
no universally agreed set of tests
2 approaches
comprehensive or big battery approach
battery of tasks designed to assess most cognitive functions
premise:
when there is a deficit, it will be detected by the battery
eg. Halstead-reitan neuropsychological test battery
disadvantages: very time consuming and some functions are not assessed in sufficient detail (eg. attention)
standardised tests
2. individualised, hypothesis-testing approach
based on particular question posed in assessment
information prior and during assessment is sued to select tests for assessing certain functions in detail
disadvantage: failing to assess particular functions because deficit is not readily apparent
usually combination of both approaches are used in clinical practice
functions assessed in npsy assessment
premorbid functioning
intellectual functioning
memory
attention
language functions
visuospatial and visa-constructional skills
executive functioning
mood, personality and behaviour
motor functioning
functions assessed in npsy assessment
premorbid functioning
cognitive functions always represent spectrums with people scoring high or low (variability)
in npsy assessment
comparison of individual test score with normative data
2 outcomes when a deficit is present
–> individual test score shows an impairment or not
functions assessed in npsy assessment
test score results if below average in impaired individuals
tests scores of individual results are below average
therefore, individual is impaired
individual requires treatment, support, pension or compensation
functions assessed in npsy assessment
test score results if above average in impaired individuals
severity of impairment of individual results if above average or the normal range
conclusion
individual is NOT impaired
no entitlement to treatment, support, pension or compensation
functions assessed in npsy assessment
relative impairment of performance
therefore
premorbid level of functioning has to be considered
problem
usually patient did not participate on any form of cognitive assessment premorbidly
consequently
premorbid functioning has to be estimated
3 most common ways
functions assessed in npsy assessment
3 most common ways to estimate premorbid functioning in relative impairment of performance testing
General demographic information
–> age, years of education, social class
individual’s best performance on any of the cognitive tests applied
tests that are relatively resistant to the general effects of brain injury
–> eg. national adult reading test
National adult reading test NART
50 phonetically irregular words
correct pronunciation of these words implies prior knowledge of them
National adult reading test NART
a study by Crawford et al 2001
high correlation between IQ scores
comparing older adults with their own IQ scores at 11 years of age
data offer reassurance regarding continued use of NART as valid estimate of premorbid intelligence in number of conditions
National adult reading test NART
Be aware
according to neuropsychological panel of American academy of neurology 1996
no neuropsych tests have shown to have consistent diagnostic validity. some tests accurately distinguish between two or three diseases when samples of patients with these diseases are assessed, but no study shown neuropsychology tests have predictive value when patients with wide variety of disorders are tested
prerequisites of assessment
selection of appropriate measures
requires
consideration of patients’ characteristics
age (eg normative data)
education (eg. education-specific normative data)
reading level
primary language (caveat: direct translations of English tests are not always adequate)
Ethnicity/cultural factors (cultural traditions, test-taking experience and attitudes towards testing) may cause variance
prerequisites of assessment
Cultural factors
immigrants come to america via Ellis Island, greeted by immigration officials
leads to
evaluation of physical, mental and other variables
leads to
failing of physical, mental or other tests
leads to
return to home country
leads to
at expense of the shipping company that had brought them
prerequisites of assessment
assumptions
assumption
- some of immigrants who failed mental tests were sent away because they did not understand English enough to execute instructions
Furthermore
- criterion against which immigrants were being evaluated can be questioned
eg
who served as the standardisation sample
how appropriate was that sample for this application
prerequisites of assessment
Diana Bossie v. State Board of Education (1970)
Children with Spanish surnames:
- 18% of student body
- 33% in classes for educable mentally retarded
however,
all testing in English
use of intelligence tests developed primarily on white children
retesting of nine Spanish-speaking children in Spanish, eight scored in the non-retarded range
prerequisites of assessment increasing cultural sensitivity
cultural sensitivity
consideration of various aspects of culture, including
verbal communication
nonverbal communication
culture-fair tests
standards of evaluation
prerequisites of assessment
verbal communication
eg. problems with use of interpreters
- one language may lack words to fully correspond to meaning of word in another language
interpreter may unintentionally change, embellish or distort information
interpreter’s own cultural norms and values may interfere
the interpreter may lack an understanding of what is important from psychological perspective
confidentiality issues may cause client to provide more limited info when interpreter is family member or friend
prerequisites of assessment
nonverbal communication
eg. eye contact
western cultures
a person failing to look at another person in the eye when speaking may be viewed as deceitful or having something to hide
other cultures
failure to make eye contact when speaking may be a sign of respect
prerequisites of assessment
culture-fair tests
cultural loading
magnitude with which cultural influence is reflected in the measured psychological variable (eg. IQ)
eg. name three words for snow
high cultural load
(items drawn from eskimo culture when many words exist for snow)
by contrast, people from Groningen would be hard put to come up with more than one word for snow
eg. culture fair test of intelligence
prerequisites of assessment
ways of reducing the cultural loading of tests
culturally loaded
- reading required
- specific factual knowledge
- scholastic skills
- recall of past-learned information
cultural loading reduced
- purely pictorial
- abstract reasoning
- nonscholastic skills
- solving novel problems
prerequisites of assessment
standards of evaluation
eg.
judgments related to certain psychological variables can be culturally relative
- schizophrenia versus voodoo
prerequisites of assessment selection of appropriate measures
good theoretical and practical knowledge of the measures used
requires
good theoretical and practical knowledge of the measures used
availability of tests diagnostic validity reliability sensitivity specificity normative data
prerequisites of assessment selection of appropriate measures
good knowledge of type and severity of disease and deficits
level of global impairment
(test selection should avoid ceiling and floor effects)
cognitive deficits (eg. attention deficit)
Physical disabilities (eg. motor deficits)
prerequisites of assessment selection of appropriate measures
consideration of referral question
diagnosis (eg. Alzheimer disease)
patient care and planning
treatment planning and remediation
treatment evaluation
research
forensic neuropsychology
prerequisites of assessment selection of appropriate measures
examples of rehabilitation procedure
evaluation of rehabilitation procedure
has 3 aims to
1. is there a change in cognitive status over time? (improvement or deterioration?)
- Is the rehabilitation programme effective?
- have rehabilitation effects generalised to non-trained items within the rehabilitated domain or to non-rehabilitated domains?
- -> leads to eg. computer training of selective attention
prerequisites of assessment selection of appropriate measures
evaluation example of rehabilitation procedure
eg. evaluation of rehabilitation procedure
eg. computer training of selective attention
- improvement on computer test
- improvement on reading task
- improvement on driving a vehicle
prerequisites of assessment selection of appropriate measures
evaluation of rehabilitation procedure pitfalls
3 pitfalls
- acute
- assessment prior to rehabilitation (10 weeks post injury)
- assessment following rehabilitation (eg. 20 weeks post injury)
- test-retest effects
- test specificity to the rehabilitated cognitive function
selection of tests that are specific to cognitive function trained in rehabilitation programme
AND
selection of tests that are independent from cognitive function trained in rehabilitation programme
(application already at baseline before any treatment)
- spontaneous variability and natural history of the cognitive deficit
- the severity of a deficit might improve because of a spontaneous recovery (even when no therapy is applied)
prerequisites of assessment
concentration
patient must be able to concentrate for time of assessment
neuropsychological assessment usually takes several hours
ensure that adequate breaks are taken (assessment should not take longer than 90 to 120 min)
impairments of attention/concentration in up to 85% of patient with brain pathology
prerequisites of assessment
comprehension
impaired comprehension makes test results invalid
ensure yourself that patients comprehend the task instructions
(no verbal comprehension difficulties, no impairment of perception)
ask patients whether they wear glasses (often patients forget to bring their glasses to assessment)
caveat: not all patients complain about their difficulties (eg. anosognosia, neglect)
prerequisites of assessment
motivation
very important and complex issue
- NPSY tests require motivation, cooperation and effort of examinees
- 5 mechanisms
- brain areas responsible for drive and initiation of action directly damaged
in some patients
inability to initiate action unless each stage of action is prompted
- motivation problems resulting from mood disorder
eg. depression in a patient
–> cannot make effort during testing
therefore overestimation of level of impairment
affects almost all cognitive test, however certain tests more sensitive
rule of thumb: the more tedious and difficult a task, the more likely is effect
