The observation of contingent negative variation with reaction times in non-human primates

Abstract

A half-century's worth of research has established the existence of numerous event-related potential (ERP) components measuring different covert cognitive operations in humans including preparing responses to anticipated events. An ERP component referred to as contingent negative variation (CNV) is believed to be an index of movement preparation and initiation during the interval between a warning stimulus and an imperative stimulus triggering a response. Using an electrophysiological technique analogous to procedures for recording scalp ERPs from humans, we show that macaque monkeys exhibit a CNV during a memory-guided saccade task. First of all, we observed the highest amplitude of CNV over the motor cortex. Second, the amplitude in CNV was related to the reaction times. Thus, we conclude that CNV observed in non-human primates like CNV observed in humans is a covert mechanism underlying the preparation and initiation of voluntary movements.