REFLEX SUPPRESSION IN THE ANTI-SACCADE TASK IS DEPENDENT ON PRESTIMULUS NEURAL PROCESSES

Reflexive responses often must be suppressed to correctly execute a vo luntary behavior. It is largely unknown why this control sometimes fai ls. To examine the neural processes responsible for these failures, we recorded single-neuron activity in the superior colliculus (SC) in be having monkeys during an anti-saccade task in which they had to suppre ss a saccade to a visual stimulus that suddenly appeared in the periph ery and generate a saccade to the opposite side. We found that the lev el and distribution of prestimulus activity of buildup neurons in the SC was highly predictive of whether a correct response or an error occ urred. A high level of prestimulus activity in buildup neurons at the location in the SC where the visual stimulus was represented was assoc iated with the generation of a reflexive saccade to the stimulus. Thes e findings suggest that the successful suppression of reflexive saccad es is dependent on prestimulus neural processes in the SC.