Figure 1.

Schematics showing task design. A, The interleaved pro-/anti-saccade task (IPAST). Each trial started with a central fixation cue (FIX), the color of which indicated the trial instruction (PRO saccade, blue; ANTI saccade, red). After a 200 ms GAP where the screen was black, a white peripheral stimulus (STIM) appeared at 10° horizontally to the left or right of where FIX had been. The participants were expected to generate a pro-saccade toward STIM or an anti-saccade away from STIM, based on the instruction they had been given by FIX. The example shows an eye position trace representative of a saccade being made during the appropriate epoch. Performing a pro-saccade on an anti-saccade trial was called a direction error. B, The free-viewing (FV) Video Task. Participants watched 10 movies (each 1 min long) consisting of 16–17 individual clips (2–4 s duration each clip).