Figure 2.

Basic manifestations of maturation on antisaccade performance

(A) Sequence of events in the antisaccade task. Left, overlap variant. The cue and fixation point overlap for 100 ms before they both turn off and signal the requirement for a saccade away from the cue. Middle, zero-gap variant. The fixation point turns off simultaneously with the cue onset. Right, 100 ms gap variant. The fixation point turns off, and after a 100 ms gap, the cue appears. Inset depicts possible locations of the target on the screen.

(B–D) Saccadic responses in young (blue bars) and adult monkeys (red bars). Eye movements were classified as directed to the target (Target; saccade within ±45° of target direction), directed to the cue (Cue; saccade within ±45° of cue direction), or intermediate (Inter; saccade more than ±45° away from both target and cue directions). Bars show mean proportions of responses of each type in the overlap (B), zero-gap (C), and 100 ms gap (D) conditions. Points show data from individual monkeys, with error bars indicating ±1 SEM (these are almost always smaller than the symbols).

(E–G) Mean reaction time (RT) from both correct and incorrect trials for the overlap (E), zero gap (F), and 100 ms gap (G) conditions. Bars correspond to mean values; points correspond to data from individual monkeys, with error bars showing ±1 SEM.