Illustration of the experimental protocol.

(a) Schematic view of a trial progression during the eye-gaze contingent paradigm used in this study. On the beginning of each trial, a fixation-cross is presented randomly on the screen, and is replaced by a face image as soon as the eye-tracker detects that the observer's line of sight lays on the fixation-cross. The yellow circles represent the observer's gaze position on the screen. Eye-fixation landing position on the seven predefined fROI (b) is controlled by the presentation of a fixation-cross located randomly in one of nine invisible quadrants on the screen, that were spatially mapped with the location of the fROIs (top). Actual gaze positions compiled over all subjects and trials for each face orientation (bottom). Gaze position for each trial is depicted with a black dot. (c) Saliency map and spatial resolution of face images and visual field map coverage when the centre of gravity of the face is fixated.