Fig. 1: Stimuli and example of oddbal sequence.

A Illustration of the stimuli used in the oddball sequence (N = 3) and in the equiprobable sequence (N = 6). B Example of the oddball sequence showing the time course of the task. Stimuli were presented for 150 ms, followed by the central cross presented for 550 ms (SOA = 700 ms). Target consisted of a standard face stimulus with no cross (participants had to detect the disappearance of the central cross).