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Outline. 1. Neuropsychological Assessment Goals of neuropsychological assessment Psychometric approach – advantages Psychometric approach – interpretation 2. IQ and Neuropsychological Testing 3. Malingering. Outline. 4. Neuropsychological Test Batteries Halstead-Reitan
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Outline 1. Neuropsychological Assessment • Goals of neuropsychological assessment • Psychometric approach – advantages • Psychometric approach – interpretation 2. IQ and Neuropsychological Testing 3. Malingering
Outline 4. Neuropsychological Test Batteries • Halstead-Reitan 5. Functions of interest to neuropsychologists • Laterality • Visual Perception • Language • Memory • Attention & Executive Control
1. Neuropsychological Assessment Goals • Diagnosis • What happened that damaged the patient’s brain?
1. Neuropsychological Assessment • Goals • Description • What went wrong cognitively, emotionally, or behaviorally as a result?
1. Neuropsychological Assessment • Goals • Tracking changes • Observe changes in patient’s performance over time, to monitor healing/worsening and effects of treatment
1. Neuropsychological Assessment – advantages • Standardized: • Repeatable instructions, presentation, and tasks • Norms • Intensive: • Multiple measures within and among wide range of domains
1. Neuropsychological Assessment – advantages • Sensitive • Valid indicators of skills, capable of detecting abilities and deficits • Scaled • Hierarchical items • Start/stop rules
1. Neuropsychological Assessment – advantages • Precise • Allows reliable, exacting quantification of relative abilities • Allows comparison within/over time
1. Neuropsychological Assessment • Interpretation • Quantitative observations: • Many tests give standardized scale scores (like Wechsler tests) based on norms
1. Neuropsychological Assessment • Interpretation • Actuarial results (e.g., Boston Aphasia Battery) – profile of subtest scores indicates nature of disorder
1. Neuropsychological Assessment • Interpretation • Cut-off scores used to make decisions • How are cut-offs set? Norm-referenced? Criterion-referenced?
1. Neuropsychological Assessment • Interpretation • Neuropsychologists also make up tests as needed – these typically are not standardized, so interpretation may be problematic.
1. Neuropsychological Assessment • Interpretation • Example: line-crossing task used to detect “neglect” following right-hemisphere brain damage
1. Neuropsychological Assessment • What do we know about the line-crossing test? What cognitive operations are involved in test performance? • Why do neglect patients fail at this test? • Is this test valid? Reliable?
2. IQ and neuropsychological testing • Estimating pre-morbid IQ may be necessary to determine whether there is actual loss of function or capacity. • Often difficult to use a regular IQ test with patients
2. IQ and neuropsychological testing • Estimating pre-morbid IQ – Clinical approaches • Education • Vocabulary • Occupation, farm size • Functional capacities
2. IQ and neuropsychological testing • Actuarial & psychometric approaches • Demographic formulas • Reading level • Subtest pattern
3. Malingering • Faking a disorder or deficit. • Important for legal and financial reasons – people sometimes fake a deficit in order to collect insurance payments, or to fraudulently obtain narcotics
3. Malingering • Tests to catch malingering usually based on fact malingerers don’t know what real deficits look like – they often show too much loss of function. • Munchausen Syndrome – psychopathology involves faking illness, but not for money or drugs • Rarely treated successfully
4. Neuropsychological test batteries • Test batteries – large sets of tests • Wide variety of tests to tap many different skills and abilities • Developed before the era of brain scanning, in part to help locate site of brain damage
To use test batteries or not? • On the plus side: • Many batteries have known psychometric properties (e.g., reliability, validity). • Use of standardized procedure permits comparison of one patient with others, even if the others are tested by different clinicians. • Tests cover a wide range of cognitive functions and behaviors
To use test batteries or not? • On the minus side: • Test-centered rather than patient-centered • Time-consuming • Patient may fail a test for many different reasons • Batteries are developed for general purposes – may lack flexibility to assess any given patient’s idiosyncratic deficits. • May reduce clinician’s potentially useful curiosity, lead to “cookie-cutter reports.”
4a. HRNTB • Ward Halstead • Ph.D. psychologist, taught in U Chicago Medical School • Through 1940s, devised and tried out many tests for use with brain-damaged patients • With his student Ralph Reitan, settled on a battery of tests that allowed comprehensive evaluation of BD patients
Reitan’s four-fold approach • Inferential decision-making using the HRNTB based on: • Level of performance • Pattern of performance • Specific behavioral deficits • Comparison of two sides of the body (right-left comparisons)
Reitan’s four-fold approach • Level of performance • Comparison of individual with normative groups of impaired and non-impaired persons
Reitan’s four-fold approach • Pattern of Performance • Examination of intra-test performance and subtest scores
Reitan’s four-fold approach • Specific Behavioral Deficits • Sensitivity to deviant or deficient performance which, of itself, points to impairment
Reitan’s four-fold approach • Comparison of Two Sides of the Body • Looking for discrepancies in test performance which may reveal weakness or lateralized impairment
4a. HRNTB • Category test • Tests abstraction and reasoning • Tactual performance test • Manual dexterity, spatial memory, tactile discrimination • Seashore rhythm test & Speech-sounds perception test • Attention, concentration, auditory discrimination • Finger tapping test • Motor speed and manual dexterity
4a. HRNTB • Trail making (see below) • Reitan-Indiana Aphasia Screening Examination • Reitan-Klove Sensory Perceptual Examination • Version of standard neurological screening test for sensory processes • Strength of Grip Test • Uses hand dynamometer • Lateral Dominance Examination
Functions of interest to neuropsychologists • Laterality • Visual Perception • Language • Memory • Attention & Executive Control
5a. Laterality • Compares functions of the L and R hemispheres of the cortex • Especially important if neurosurgery is planned: where are language functions? • Language functions are in left hemisphere in most people, bilateral in some • Annett Handedness Questionnaire
Annett Handedness Questionnaire Please indicate which hand you habitually use for each of the following: (R, L or E) 1. Writing 2. Throwing a ball 3. Holding a racquet 4. Striking a match 5. Cut with scissors 6. Threading a needle 7. At top of broom 8. At top of shovel 9. To deal cards 10. To hammer a nail 11. To hold a toothbrush 12. To unscrew a lid There are several ways to score this test
5b. Visual Perception • Visual field deficits • Informal assessment by clinician • More precise assessment requires special optometry equipment.
5b. Visual Perception • Agnosia – inability to recognize familiar objects visually. • To test – ask patient to name various objects • Meaning of objects has not been lost –it’s a deficit of visual recognition.
Visual agnosias • visual object agnosia – inability to identify common visual objects • prosopagnosia – inability to recognize familiar faces • color agnosia – inability to discriminate between colors and to name colors • simultanagnosia – visual perception of simultaneously presented objects is impaired
Figure/ground discrimination – separate figure from background
The embedded figures test – task is to find all the objects in this figure.
Visual Memory • Rey-Osterrieth figure • complicated, abstract figure (next slide) • patient looks at it briefly then asked to reproduce the figure from memory • scoring is quite complex • assesses visual memory, visual construction skill
5c. Language • A very important function for humans, typically mediated by left hemisphere • Expressive and receptive language can be independently lost or spared
5c. Language • Batteries include Boston Diagnostic Aphasia Examination and Western Aphasia Battery (developed at UWO School of Medicine) • Task-specific tests used with patients having comparatively isolated dysfunctions
Boston Diagnostic Aphasia Examination • Oral Expression – word repetition, body part naming, visual confrontation naming • Writing • Auditory comprehension: Body part identification • Understanding written language: Word picture matching.
Task-specific tests • Graded Naming Test or Boston Naming Test - both assess ability to name objects. • Token Test - detects non-obvious loss of receptive language • Pyramid & Palm Trees Test - tests the understanding of words
Graded Naming Test examples – test has 30 of these, presented in order of increasing difficulty Boston Naming Test examples
Pyramid Palm Tree Fir Tree 3 Word Version 3 Picture Version Pyramid and Palm Trees Test – which one of the two lower items goes with the upper item?
5d. Memory • Amnesia is loss of episodic (personal) memory, which may include knowledge of public people/events • Two distinct kinds of amnesia: • Retrograde • Anterograde
5d. Memory • Retrograde • loss of memory for events from patient’s past • patient asked to retrieve old events • Anterograde • loss of ability to store new memories. • patient exposed to new information, then memory for that information tested