Do “brain fog” complaints of some drug treated cancer patients reflect the effects of depression or injury to the brain?
By: Leslie Ruthven, Ph.D. retired clinical psychologist
Email: dr.les.ruthven@gmail.com
Health Blog: www.ruthvenassessments.com
The question posed in the title has been going on ever since the onset of chemotherapy, yet the medical profession has not as yet come to a definitive answer to the source or sources of such complaints. I will offer in the following a way to find the correct answer to the question. The method used, however, must have at least the following characteristics:
- We need to take a measure of at least 50 diagnosed cancer patient’s cognitive ability before, during and after the conclusion of chemotherapy.
- The cognitive test would have to be self-administered, brief, inexpensive ($25.00 perhaps), online, a performance test taken on a desk top computer for a person with average computer skills, a reading level of it least the 8th grade, and a test with little or no practice effects on serial testing.
The Ruthven Impairment Assessment (RIA)
The writer believes the RIA is the only behavioral performance test that meets all of the characteristics in number 2 above. The RIA, or any behavioral test, requires both norms and a demographic description of the normative group. The RIA performance norms included 55 college students at Wichita State University, ages 17 to 58 years, and approximately the same number of males and females. No gender performances differences were observed. Each subject took the RIA 3 times over a 10-day period. On the analysis of variance of the 3 test sessions there was no statistical difference in the performance scores for each of the 3 test sessions; session I group scores were taken as the test norms (Email the writer for the norms).
The RIA consists of 5 brief subtests (10 items in each of the first 4 subtests and 13 on subtest 5, the most cognitively and intellectually challenging of the battery. Structural brain damage requires significant impairment on subtests 4 (attention/memory) and 5 (anticipatory thinking and executive abilities) while “reversible” Ci impairment shows difficulty on subtests 1—4; however, when anticipatory thinking and memory are in the non-impaired range, the subjects are likely to have “reversible” brain impairment at least presently.
Subtest 1 is a measure of simple RT (“press the space bar to any lighted number on the clock face as quickly as you can”); for subtest 2 “press the space bar to any odd clock number; for subtest 3 (“press the space bar to the number following two even numbers except if that number is a 3 or a 10”. The number exceptions change from test to test.
Reaction time patterns reflecting severity of Ci
Norms on the RIA finds that RT on both subtests 2 and 3 are each 50% slower than simple RT; when RTs on subtests 2 and 3 are significantly greater than this 50% we have a case of either reversible or structural brain damage depending on the pattern and severity of slowness. Subtests 4 and 5 require the subject to manipulate the mouse and to left click on the number(s) as instructed. Subtest 4 requires the subject to repeat a series of 3, 4, 5 and 6 lighted numbers to test recall. Subtest 5, anticipatory thinking, is the most powerful higher level cognitive asset in the test and when substantially impaired the indication is some form of structural brain damage.
Serial RIA testing of chemotherapy treated patients to determine the nature of brain fog and memory complaints of these patients.
Prior to the start of chemotherapy 50 or more cancer patients take the RIA initially as a cognitive baseline. Next the patients take the RIA serially while on the medication. If RIA performance declines while on the medication, consider stopping the drug. It is advisable after any chemotherapy drug termination to renew serial testing with the RIA until performance stabilizes.
