Guide to ReportsNEUROPSYCHOLOGICAL ASSESSMENT LABPAUL JONES, ED.D.
UNIVERSITY OF NEVADA, LAS VEGAS
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TEST INSTRUMENTS:
Series Two
The Automated Neuropsychological Assessment Metrics Battery (ANAM), a clinical subset of instruments developed by the Office of Military Performance Assessment Technology, is comprised of a series of cognitive tasks administered and scored with a computer. Organized as a Tester's Workbench (TWB), a variety of task combinations can be created. ANAM (V1.0), for example, contains four battery subsets which differ in the number of tests, number of stimuli presented in each test, and so forth. This allows the user to construct batteries tailored for specific needs and anticipated levels of cognitive function. The common feature in the ANAM scales is highly-structured, repetitive information processing tasks with well-defined stimuli and simple response modes. Several scores are available for each scale including task accuracy, mean response time for accurate responses (ms), and an efficiency score defined as the number of correct responses per minute.
Participants in the series two studies completed five scales drawn from the ANAM/TWB batteries. The scales included in this study were:
COGNITIVE PROCESSING
1. Simple 2-Choice Reaction Time- ANAM/TWB
2. Procedural Reaction Time- standard/degraded stimuli- ANAM/TWB
3. Mathematical Processing- ANAM/TWB
4. Spatial Processing- simultaneous- ANAM/TWB
5. Matching to Sample- ANAM/TWB
Also included in the series two studies were two cognitive scales previously developed by this investigator with intent to provide instruments equally applicable for persons who have visual disability and for the sighted population. Both use auditory rather than visual stimuli with the keyboard rather than computer mouse as the primary response mode.
ADAPTED COGNITIVE SCALES
6. CogAttention
7. CogMemory
Trait level personality assessment was provided in the series two studies with another instrument previously developed by this investigator intended for equitable use for persons with and without visual disability. CogStyle is measure of core personality characteristics using stimuli selected to minimize, if not eliminate, the influence of visual experience on the response.
TRAIT PERSONALITY MEASUREMENT
8. CogStyle
Detailed descriptions of the scales are provided below. All testing was completed in a single 1/2 hour session. The actual test trial was preceded by a practice trial with comparable, but fewer, stimuli. The practice session was intended to familiarize the subject with the task. Feedback (correct or incorrect) was provided in the practice trial. For each of the ANAM/TWB scales, the number of items, stimulus duration, and time allowed for response were chosen to facilitate comparison of the participant's scores to results in published studies.
Administration of an ANAM/TWB scale provides a number of summary scores for each scale as well as individual item accuracy and response times. The primary summary scores used in the series one studies are: 1) percentage of correct responses, and 2) efficiency (defined as number of correct responses per minute). Percentage correct is limited by ceiling effects, and accuracy at the 90+ percent level is common. The efficiency score, however, may (Levinson & Reeves, 1997) be limited only by an individual's level of CNS function.
Schlegel, Gilliland, and Crabtree (1992) conducted a series of test-retest reliability studies with ANAM/TWB cognitive scales with intervals of 30 minutes, 24 hours, one week, and three weeks. They found that the low ceiling on the percent correct scores seriously compromised the obtained accuracy coefficients; overall scores were so high that little variability was retained in the measurement. Test-retest reliabilities based on response time, however, were typically at acceptable levels (e.g. .80 to .90).
This classic two-choice reaction time task was added for the series two studies to provide a fundamental measure of reactivity with minimal cognitive loading. In this task, the symbol "*" or "o" is presented on the computer screen. The subject responds simply by clicking the left mouse button or right mouse button to identify which symbol is on the screen. Stimuli (6 in the practice trial, 30 in the test) are presented on the screen for up to 8000 ms with a maximum of 9000 ms allowed for response.
In the standard version, the numerals 2,3,4, and 5 are presented on the computer screen, one at a time. The subject is requested to respond by clicking the left mouse button if the stimulus is a 2 or 3, and the right mouse button if the stimulus is a 4 or 5. Stimuli (6 in the practice trial, 37 in the test) are presented on the screen for up to 8000 ms with a maximum of 9000 ms allowed for response.
For the series two studies, after each participant completed the Procedural Reaction Time test in the standard format, it was readministered in a "degraded" format. In the degraded version, the task demand was identical, but stimuli on the screen were visually distorted and more difficult to identify.
There are a number of versions of this scale. In some applications there is a mixture of alphabetic characters and numbers. It is also possible to have an unpredictable time interval between stimuli. The total length of the test can be a few minutes or an extended time period. The common feature in all of the variations is a purpose to test a subject's ability to continue making decisions and rapid responses to visual symbols for nonstop periods.
Continuous performance tasks such as this have been shown to be effective in detecting brain damage with the impairment likely to be revealed in the form of attentional lapses rather than as a steady decline of detection efficiency (Rosvald, et al., 1956). Sykes, Douglas, and Morgenstern (1973) reported that hyperactive children detect fewer signals and make more overall incorrect responses than their normal counterparts, with particular evidence of decreasing level of performance over extended time periods. Levinson and Reeves (1997) found differences in the predicted direction among patients classified as marginal-mild impairment, mild-moderate impairment, and moderate impairment. All of these individuals had suffered traumatic brain injuries, most from automobile accidents.
In summary, Procedural Reaction Time is a cognitive vigilance task. It is a short scale requiring sustained attention performance and would be susceptible to any number of conditions known to effect attention processes (e.g. brain damage, sleep loss and drugs). It would appear to tap the "attention" function in the contemporary PASS theory (Naglieri & Das, 1990) built on Luria's model of neuropsychological functions.
In this test, subjects perform two mathematical operations (addition and/or subtraction) on sets of three single-digit numbers, e.g., 5+3-4 = ?. The subject is instructed to read and calculate from left to right and determine whether the answer is greater than or less than five, responding by clicking the left or right mouse button. Stimuli (5 in the practice session and 25 in the actual test) are displayed for up to 14900 ms with 15000 ms allowed for response.
The purpose of this self-paced mental arithmetic task is to test a subject's information processing resources associated with working memory. Specifically, the subject is required to: (a) retrieve information from long term memory, (b) update information in working memory, (c) sequentially execute different arithmetic operations, and (d) perform numeric comparisons. The task is presumed to tap resources that are primarily associated with central processing. Furthermore, this task involves relatively basic central processing activities such as information manipulation or transpositions based on implicit or memorized rules.
The mathematical processing test probably taps the "successive" (sequential) function in the PASS theory (Naglieri & Das, 1990) of neuropsychological function. Studies suggest that this task is sensitive to the drug effects if the drug disrupts working memory processing. In their study of individuals in a traumatic head injury program, Levinson and Reeves (1997) found the math processing test sensitive in differentiating extent of traumatic brain injury in adults. Gastaldo, Reeves, Levinson, and Wegner (1997) also found that the math processing task was sensitive to symptoms of hyponatremia in a sample from the USMC.
In this test, two four-bar histograms are presented simultaneously on the monitor screen. The histogram on the right is rotated. The subject is requested to determine whether the two histograms are identical in shape and respond by clicking a mouse button.
In the practice trial there are 5 stimuli (items). In the actual test there are 25 stimuli. Stimuli are displayed for up to 8000 ms with up to 9000 ms allowed for response.
This task is designed to examine the subject's ability to mentally rotate histograms prior to making a same/different judgment about them. An original version of this task was created by Fitts et al.(1952) and the general paradigm is often referred to as the Fitts Histogram procedure. This visualization task appears to tap the "simultaneous" function in the PASS (Naglieri & Das, 1990) model.
Comparable tests of the spatial orientation factor have been shown to be sensitive to cyclical variations in cerebral hemisphere arousal (Klein & Armitage 1979). Along with the scales described above, this spatial relations scale was apparently sensitive to traumatic brain injury (Levinson & Reeves, 1997) and symptoms of hypnotremia (Gastaldo, Reeves, Levinson, & Wegner, 1997) .
This task is designed to assess the subject's ability to quickly and accurately choose a test stimulus which is identical to a standard stimulus presented previously. The test taps short term spatial memory and pattern recognition skills
The subject is shown a single 4 by 4 matrix centered on the screen. The matrix has cells of two colors (red and yellow) with the number of cells of each color randomly determined for each stimulus. After viewing the sample stimulus for a time adequate for committing the stimulus to memory, the subject initiates the presentation of the test stimulus by clicking a mouse button. The test stimulus consists of two 4 by 4 matrices, side by side on the screen. One of the matrices is identical to the previously presented standard stimulus; the other is different. The subject selects the identical stimulus, responding by clicking the left or right mouse button. The practice session with this task included five trials (items); the actual test used 25 trials. The stimulus was displayed for up to 14900 ms with 15000 ms allowed for response.
The Matching to Sample task was not included in the battery administered by Levinson and Reeves (1997) to the sample of persons with TBI. The efficiency score was found to be sensitive to the symptoms of hyponatremia (Gastaldo, Reeves, Levinson, & Wenger, 1997). It was included in the series one studies to confirm the predicted positive relationship with the spatial processing scale with a view toward possible future use as a second measure of the simultaneous neuropsychological processing function.
CogAttention is one of three scales developed by the author to provide equity in assessment for persons with and without visual disability. CogAttention is a two part measurement of basic attending and organizing of information. In part one, two tones are presented; the task is to identify whether the first was a higher pitch, the second was a higher pitch, or if they were the same. There are ten comparisons (items). In part two, the person hears two series of tones. The second series is identical to the first except that one of the tones is different in the second series. The task is to identify which tone is different. Part two also has ten items.
With a free password which is obtained from the author, CogAttention can be administered, scored, and interpreted via the Internet/WWW at no cost per use. Additional description and development history of this instrument is available in a related report.
CogMemory is another instrument specifically developed for use by persons with visual disability and the sighted population. CogMemory uses memory span for digits to measure short-term memory, attention, and sequential processing. The subject listens to a series of numbers and then enters the numbers using the keyboard.
The subject responds to eight different memory span items with the number of digits in each series ranging from 5 to 9. The format of scoring each digit is used, rather than an all-or-none score for each set.
This instrument is also available for administration, scoring, and interpretation via the Internet/WWW. The password for use at no charge is obtained from the author. Additional description and development history for this test is available in a related report.
CogStyle is the third of the instruments developed/adapted for equitable use by persons with and without sight. CogStyle is designed to assess core personality characteristics and is included in this context with recognition of evidence of a relationship between personality traits and cognitive performance on some scales.
The rationale and development history is provided in a related report. A password allowing the test to be taken via the Internet/WWW is available at no charge from the author.
References
Fitts, P. M., Weinstein, M. , Rappaport, M., Anderson, N., & Leonard, J.A. (1956). Stimulus correlates of visual pattern perception: A probability approach, Journal of Experimental Psychology, 51, 1-11.
Gastaldo, E., Reeves, D., Levinson, D., & Wenger, C.B. (1997). ANAM normative data: USMC-1995 hyponatremia outbreak studies. San Diego, CA: National Cognitive Recovery Foundation.
Klein, K., & Armitage, R. (1979). Rhythms in human performance: 1 1/2 hour oscillations in cognitive style. Science, 204, 1326-1328.
Levinson, D.M., & Reeves, D.L. (1997). Monitoring recovery from traumatic brain injury using Automated Neuropsychological Assessment Metrics. Archives of Clinical Neuropsychology, 12, 155-166.
Naglieri, J.A., & Das, J.P. (1990). Planning, attention, simultaneous, and successive cognitive processes as a model for intelligence. Journal of Psychoeducational Assessment, 8, 303-337.
Rosvald, H. E., Mirsky, A.F., Sarason, I., Bransome, E.D., & Beck, L.M. (1956). A continuous performance test of brain damage. Journal of Consulting Psychology, 90, 343-350.
Schlegel, R.E., Gilliland, K., & Crabtree, M.S. (1992). Development of the UTC-PAB Normative Database: Technical Report. Springfield, VA: National Technical Information Service.
Sykes, D. H., Douglas, V.I., & Morgenstern, G. (1973). Sustained attention in hyperactive children. Journal of Child Psychology and Child Psychiatry, 14, 213-221.
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