How emotional arousal and valence influence access to awareness.

The effect of emotion on visual awareness is largely unknown. Pairs of natural images were presented side by side on a screen in a binocular rivalry setup. The amount of time that each image of a pair dominated perception was computed. Our results showed: (A) A main effect of arousal: Dominance durations of the more arousing picture of iso-valence pairs were longer. (B) No effect of valence: Dominance durations of pleasant and unpleasant pictures of iso-arousal pairs were similar. (C) An interaction between arousal and valence: The more pleasant picture of iso-arousal pairs of low arousal level dominated conscious perception. The less pleasant picture of iso-arousal pairs of high arousal level dominated conscious perception. Our findings suggest that the emotional content of a stimulus affects the extent to which it dominates awareness. While arousal and valence interactively affect access to awareness, only arousal exerts an independent control of such access.