Processing speed interacts with working memory efficiency in multiple sclerosis.
Information processing speed was assessed using the visual threshold serial addition test (VT-SAT), a computerized modification of the PASAT designed to assess processing speed by controlling for performance accuracy. Persons with MS (N=43) and healthy individuals (N=32) were administered the VT-SAT varying working memory loads (1-back versus 2-back). Results indicated that at the lower working memory load (1-back) all individuals with MS were able to achieve a working memory performance level equivalent to healthy individuals, but required significantly more processing time to do so. In contrast, at the higher working memory load (2-back), about 70% of MS participants were able to achieve a performance level equivalent to healthy individuals, but again required significantly more processing time. The results are discussed in the context of the dynamic nature of the relationship between processing speed and working memory performance, emphasizing the dependence of this relationship on other cognitive and disease-related factors.
Kessler Medical Rehabilitation Research and Education Corporation, West Orange, NJ, USA.
Jean
J
Lengenfelder
Deborah
D
Bryant
Bruce J
BJ
Diamond
Jessica H
JH
Kalmar
Nancy B
NB
Moore
John
J
DeLuca
D000328:Adult; D016022:Case-Control Studies; D002540:Cerebral Cortex / Q000503:physiopathology; D006801:Humans; D008568:Memory / Q000502:physiology*; D008606:Mental Processes / Q000502:physiology*; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000503:physiopathology / Q000523:psychology*; D009483:Neuropsychological Tests; D011930:Reaction Time / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology