Week 2: Neuropsychological Assessment Flashcards
What is psychological assessment?
An involved process consisting of looking through history, undertaking an interview, giving some sort of test (questionnaire).
What is a neuropsychological assessment?
Neuropsychological assessments assess cognitive function:
- study of behaviour by interview and standardized tests
- looking distinctly at brain function
Difference between neuropsychological assessment vs testing:
Neuropsychological testing: the process of administering a test, scoring it, and interpreting the test scores (undertaken to answer clear cut questions like ‘What is Jane’s IQ’?).
Neuropsychological Assessment: involves multiple components, one of which is the neuropsychological testing, to solve more complex issues.
Neuropsychological tests are tools utilized during a neruopsychological assessment.
What is the purpose of neuropsychological assessment?
- Allows for clearer delineation of cognitive profile
- Identify cognitive strengths and weaknesses (e.g. veterans who have worked in highly trained roles after high school and don’t know what their strengths and weaknesses are as an adult)
- Hypothesis testing
- Assist with diagnosis, management and rehabilitation (assessing cognition to understand how the pattern of people’s scores fit profiles of depression / dementia)
- Longitudinal monitoring of cognitive functioning (testing if long-term patients are stable or declining - helpful for management and rehab)
- Baseline vs follow up assessment (treatment efficacy)
- Assessments for specific purposes (decision making capacity, driving ability, etc)
Neuropsychological assessment process
Can go from 2 to 8 hours (as it is dependent on the referral question)
Involves:
- reviewing the referral (what is it asking us?)
- reviewing patient medical record
- conducting patient and informant interviews (what are the concerns, background, what led to the referral)
- administration of standardized tests
- test scoring
- test interpretation
- neuropsychology report
Tests need to have good psychometric qualities!
Reliability = accuracy, consistency, and stability of test scores across situations
Validity = the degree to which evidence supports the interpretation of test scores for their intended purposes (does the test measure what it claims to measure)
- lowest reliablility across processing speed tests
What is assessed?
- Orientation: how alert and aware they are of current surroundings
- Premorbid intellectual functioning: estimate of where they ‘should’ be functioning, what their IQ should be
- Effort: is someone is exaggerating their impairment, or not trying hard enough
- General intellectual ability (IQ)
- Attention / working memory
- Processing speed
- Language
- Visuospatial skills
- Memory
- Executive functioning
- Motor skills
- Mood and behaviour
Neuropsychological test interpretation:
- obtain scores compared to normative data for relevant age / education group
- compare current performance to premorbid expectations (important to do this in order to take into account a decline in ability when the result isn’t ‘severe’)
- further calculations to determine strength and weaknesses
- consider cognitive performance in conjunction with neuroimaging, behaviour on testing, informant reports, motivation level
Note: important to transform those raw scores onto a standardized scale
Challenging assessments:
CALD patients - many tests are geared to a Western type of education, or have a big language component. We can use an interpreter, or test someone in another language.
Aphasias
- Expressive aphasias (trouble communicating), we can still do quite a comprehensive assessment, but relying more on visual tasks
- Receptive aphasia (trouble understanding), you don’t know if their poor performance is because they have trouble understanding the task, or if that’s the true level of their skill.
Significant hearing & visual deficits
- can use more verbal tests (visual) or AUSLAN interpreters
Comorbid psychiatric illness
Differential diagnosis in patients with global deficits –> if someone has declined to the point where everything is really low, we can’t really determine the subtype / cause of the dementia because the cognitive patterns are masked by the level of impairment
Patients who obtain a score of 0
- means the floor the test isn’t low enough to test the abilities of the patient - we need to find a simpler test
What are the 2 approaches to psychological assessment?
Fixed: everyone does everything - more quantitative, focuses on the test scores rather than the behaviour your observe and information that is provided.
- involves Halstead Reitan Neuropsychological battery (6-8 hrs)
- Luria Nebraska Neuropsychological Battery (1.5-2.5) - 14 different types of tests, working with only one set of tests by one test maker
Flexible: choosing your approach to answering the referral question based on your hypothesis –> selecting the most relevant test
- takes around 2.5 hours
- be more flexible without any planned tests
- has more emphasis on the patient’s approach to the task, the types of errors they make (rather than total scores)
–> Flexible battery
–> Process approach (most qualitative)
Fixed battery approach - advantages and disadvantages
- broad range of tests covering broad spectrum of cognitive functioning
- standardized procedures allows comparison across patients
- reliable scoring methods (particularly important in medicolegal settings)
Disadvantages
- time consuming and crude
- some test are quite redundant
- tests are not always geared to deficits (you may not capture all the specific needs of referral question)
- limits exploration and hypothesis testing
Flexible battery approach
Adv:
- briefer
- more specific
Disadv
- more qualitative than quantitative
- too much variability
- can be impacted by personal preference and economic factors (finance, time, etc)
Composite battery approach:
- middle ground between fixed and flexible
- smaller battery of tests used to sample various cognitive domains
- results used as a platform to conduct more specific testing in certain areas or elucidate nature of deficits
- both quantiative and qualitiative
- emphasizes hypothesis testing
I.e.
you go into a setting with relatively fixed battery - you always administer those tests, but then look at the referral question and make changes to the battery to get at specific concerns.
Orientation assessment
Starting off with orientation questions to get a sense of awareness of surroundings:
then orientation to day and time
i.e. what is the day, date, month, year, season
i.e. which building, floor, town, state, country
Premorbid intellectual functioning test
Testing irregular words (words that don’t follow sound rules) is an example of a test that is quite resistant to brain injuries.
An alternative is a general knowledge test that tries to sample literature knowledge, historical knowledge, geography, science
e.g. ‘What day comes after Friday’
e.g. ‘What is a ruler used for?’
