DISSOCIATION OF VISUAL-DISCRIMINATION FROM SACCADE PROGRAMMING IN MACAQUE FRONTAL EYE FIELD

To determine whether visual discrimination in macaque frontal eye fiel d (FEF) is contingent on saccade planning, unit activity was recorded in two monkeys during blocked go and no-go visual search trials. The e ye movements made by monkeys after correct no-go trials, in addition t o atl attenuation of the visual responses in no-go trials compared wit h go trials, indicated that covert saccade planning was effectively di scouraged. During no-go search trials, the activity of the majority of neurons evolved to signal the location of the oddball stimulus. The d egree and time course of the stimulus discrimination profess observed in no-go trials was not different from that observed in go trials. We conclude that the discrimination of a salient visual stimulus reflecte d by FEF neurons is not contingent on saccade production but rather ma y reflect the outcome of an automatic visual selection process.