Fig 1.

Structure of the behavioral task. On each trial, four cue stimuli were serially presented for 1 s each. The stimulus set contained one, two, three, or four intact faces, with the remainder of the images composed of scrambled faces. A trial with a memory load of three faces is illustrated here. Participants were instructed to remember all of the intact faces across an 8 s delay period. Following the delay, a probe face appeared for 1 s, and participants made a button press response indicating whether or not the probe face matched any of the cue faces. After responding, participants were instructed to fixate on a crosshair during a 16 s inter-trial interval (ITI).