Electroencephalographic correlates of delayed-alternation and visual discrimination learning in rhesus monkeys.

Abstract

Trained 4 female monkeys on a 5-sec delayed-alternation (DA) task and on a simultaneous visual discrimination task. An EEG was recorded through chronically implanted electrodes from dorsolateral frontal cortex (sulcus principalis), inferotemporal cortex, and caudate nucleus. Prestimulus and preresponse EEG amplitudes and frequencies were analyzed for 3 levels of performance for each task. For both frontal and caudate placements: (a) on the DA task, prestimulus voltage was highest at the intermediate performance level, and the inverted- shape was statistically significant; (b) there was a significant task difference for the prestimulus but not for the preresponse, interval. For the inferotemporal placement a significant task difference was found for preresponse, but not for prestimulus, amplitudes. (18 ref.) (PsycINFO Database Record (c) 2006 APA, all rights reserved)