FIGURE 1.

Schematic overview of the spatial attention task. On each trial, participants were presented with a cue, and after a 900 or 1500 ms interval, with a target. The cue indicated that the target was more likely to appear in the left (L) or right (R) hemifield (attention condition, 75% of trials), or contained no information about the likely location of the target (N) (neutral condition, 25% of trials). After a variable delay interval, a target (a horizontally or vertically oriented Gabor patch) and a distractor (a diagonally oriented Gabor patch) stimulus were briefly shown simultaneously in opposite hemifields. Participants had to report the orientation of the target stimulus with a button press. On 75% of the trials in the attention condition the target appeared at the cued location (valid condition), while on the remaining trials the target appeared at the uncued location (invalid condition). The target and distractor were followed by a mask.