Timing and magnitude of frontal activity differentiates refixation and anti-saccade performance

EEG data were recorded while 10 subjects generated refixation saccades towa rds a visual target and antisaccades away from a visual cue. Theoretically, the same basic neural circuitry supports refixation and correct anti-sacca de performances, with additional activity in primarily dorsolateral prefron tal cortex circuitry supporting antisaccade-associated inhibitory processes . Analyses demonstrated that sensory registration of visual stimuli is simi lar for refixation and anti-saccade conditions. Increased frontal brain act ivity at 5 and 15Hz was observed preceding correct antisaccades when compar ed to refixation saccades. These analyses provide specific information sugg esting that 160-60ms before saccade generation is the critical period for r esponse inhibition. NeuroReport 12:1863-1868 (C) 2001 Lippincott Williams & Wilkins.