Last updated on January 6th, 2024 at 08:34 am
What can a 15 minute test tell you about the brain?
By Les Ruthven, Ph.D. clinical psychology
Email: lruthven.mafinearts@gmail.com
Blog: www.ruthvenassessments.com
The Ruthven Impairment Assessment (RIA) is an online, brief, computer delivered, neurocognitive performance measure of brain impairment (Ci), which is a major public health problem that is under the radar to most physicians and their patients. The computer screen has task instructions on the left of the screen and a standard 12 number clock face upon which the subject responds by bar pressing and use of the computer mouse.
On the RIA task #1 is a measure of simple reaction time (“Press the space bar when any clock number is lighted), task #2 is complex RT (“Press the space bar only to even clock numbers”), and task #3 is conditional RT (“Press the space bar to the clock number following two even clock numbers except for the designated two clock numbers”). Task #4 (measuring attention/memory) requires use of the computer mouse and left clicking on the clock numbers according to the instructions. The subject, when ready after reading the instructions left clicks on the clock to start the task; the subject replicates the presented lighted series by operating the mouse on two sequential series of 3 clock numbers, two series of 4 clock numbers, two series of 5 clock numbers and then two series of 6 clock numbers. Task 5, the most cognitively demanding task, is performed by manipulating the mouse and left clicking on two clock numbers as directed in the instructions. On task 5 there are 13 items (the first are very easy and more explanatory in nature); the subject is presented with a series of 5 clock numbers in sequence. The S is instructed to consider a theme or pattern in the series and left click on two clock numbers that would continue or complete the theme or pattern. For example, if the series were the numbers 1,2,3,4,and 5 the subject would click on 6 and 7 to continue the pattern and with such a response the word Correct would appear on the clock face. Task 5 is considered to be a measure of anticipatory thinking, which is by far the most cognitively challenging task of the RIA tasks.
The following are RIA performance norms for 55 Wichita State University college students, 15 of whom took the test with self-administration and 40 of whom had some assistance by a test monitor to access the test. Scores of the 55 students were combined when there were no performance differences between the two groups. Subjects were ages 19 to 58, there were no gender performance differences on any of the measures and there was a slight slowing down in speed of mental processing (the 3 RT tasks) and memory (task 4) with age but in the group age had no effect on anticipatory thinking/complex problem solving on Task 5. The Ss took the RIA 3 times over a 10 day period (never 2 days in a row) and the analysis of variance on the 3 test session scores found no significant performance differences over time. There seems to be little or no performance improvement over time as long as cognitive status is unchanged between testings.
The following RIA performance norms were taken from the first test session for the normative group (on the left) and on the right are “ball park” scores in the impaired range (one standard deviation in the impaired direction). There are 10 items on each of the RT tasks, the highest score on task 4 is 8 and 13 is the highest score on task 5.
| RIA WSU Student Norms | RIA scores in the Impaired range |
| Subtest #1 Mean correct 9.27 | C. 8.00 or fewer correct |
| Mean RT 0.33 | M RT 0.43 or slower |
| Subtest #2 Mean correct 8.63 | C. 7.00 or less |
| Mean RT 0.50 | M RT 0.60 or greater |
| Subtest #3 Mean correct 8.27 | C. 5.68 or less |
| Mean RT 0.51 | 0.65 or greater |
| Number exception errors 0 | 2 of 2 possible errors |
| Subtest #4 7.31 out of 8 | 6.48 or less |
| Subtest #5 | |
| # correct out of 13 items 9.59 | 7.00 or less |
Standard deviations are also available from this writer on these 9 measures.
Reaction time in cognitively normal persons. Complex and conditional RTs are equivalent and approximately twice as slow as simple RT. Impaired persons are more than 50% slower on task 2 in relation to task 1 and the degree of difference reflects severity of the impairment as does substantially slower RT on task 3 vs. task 2. The latter may reflect the more complex instructions on task 3 vs. task 2 instructions, which seems to give impaired persons more difficulty than the instructions on task 2. Rarely a CI normal person will make 1 or 2 number exception errors on task 3 but this will be recognized by the clinician because all other performances are in the normal range. What if all RTs are in the impaired range but RT on tasks 2 and 3 are equivalent? What may be going on with the subject? Consider the possibility of malingering since the 3 RTs are substantially slow but the pattern is not those of cognitively impaired persons!
The developer of the RIA suspects that some impairment of mental processing speed is consistent with both reversible and irreversible brain impairment but if these skills are completely intact one should be hard pressed to make a diagnosis of impairment despite performances on tasks 4 and 5. If performance on task 5 is in the normal range for the subject’s educational and intelligence levels one might think (if other performances are in the impaired range) the brain impairment is reversible. At this stage of RIA development impairment on task 5 probably reflects static or progressive brain damage depending on the test pattern as a whole. AZ cases are expected to have greater impairment on task 4 (memory) and greater impairment on task 5 may suggest more frontal lobe impairment. Malingering or faking bad on the test may be considered if the performance pattern of the subject is not consistent with that of a cognitively normal person or cognitively impaired persons.
The RIA performance may be able to differentiate impairment of PTSD cases from TBI cases especially the level of performance on task 5.
The above will of course be modified as more clinical and research data is collected. The RIA was never designed to make a definite diagnosis by itself but it was designed as a bridge to enable the clinician to arrive at the correct diagnosis more efficiently and more cost effectively.
Interested psychologists/neuropsychologists may obtain 25 RIA testings without cost to evaluate the RIA for clinical and research use. The current charge for the RIA is $12.00 per test. The RIA, in addition to the test, includes an optional health history (also current medications) for each person tested and a 10 item symptom/behavior survey, all of which are retained in the data base for each person tested.
