Sex differences in gaze patterns while viewing dynamic and static sexual scenes

Abstract

Objectives: Faces and bodies serve as important cues of physical attractiveness and reproductive fitness. Previous studies indicate that there are sex-related differences in the visual processing of erotic stimuli. We investigated gaze patterns and sex differences during sexual perception.

Study design: We measured the eye movements of 43 male and 67 female subjects while viewing sexual scenes (intercourse; Experiment 1) and static erotic stimuli (nude and clothed men and women; Experiment 2) in a cross-sectional study.

Main outcome measures: For each region of interest (ROI; face, chest, genitals, back) we computed mean pupil size, gaze duration, first fixation latency and first fixation duration. Intersubject correlation of eye movements (eISC) was computed to assess similarity of gaze patterns across viewers.

Results: Dwell times were the longest for faces and faces were the most likely to be looked at first. In Experiment 1, males looked more at female chest, buttocks, and genital areas while female participants looked more at male faces. In Experiment 2, faces received more fixations for clothed stimuli, whereas chest and genital areas received more fixations for nude stimuli.

Conclusions: Sex differences during sexual perception are larger for static versus dynamic stimuli. Faces are prioritized over sexual signals, and visibility of sexual cues increases saliency of the sexually relevant body regions. The preference for faces even when viewing sexual intercourse may reflect both the importance of facial characteristics in mate selection as well as the role of facial expressions in evaluating partner satisfaction while having sex.

Keywords: Attention; Emotion; Eye-tracking; Sexual perception.