PREFRONTAL COGNITIVE-PROCESSES - WORKING-MEMORY AND INHIBITION IN THEANTISACCADE TASK

Recent research suggests 2 principal processes are assessed in many ne uropsychological tests of prefrontal functioning: the ability to keep transient information on-line (working memory) and the ability to inhi bit prepotent, but incorrect, responses. The current studies examined the hypothesis that taxing working memory beyond some threshold can re sult in decreased inhibition, resembling the errors committed by patie nts with prefrontal dysfunctions. Across 3 studies, 70 nonpatient subj ects were tested on the antisaccade (AS) task (D. Guitton, H. A. Bucht el, & R. M. Douglas, 1985)-a task sensitive to inhibitory deficits. Su bjects were required to look in the opposite direction of a flashed cu e, inhibiting the reflexive tendency to saccade to the cue. Subjects p erformed concurrent tasks that varied working-memory load. The results indicated that conditions with the highest working-memory load produc ed inhibitory errors comparable to patients with prefrontal dysfunctio ns. The findings are discussed in terms of the interaction between wor king memory and the inhibition of prepotent responses.