Memory, perception, and evaluation of emotional stimuli: the effects of oral contraceptive use, sex, and gender

Abstract

Little research has examined if oral contraceptive (OC) mood side effects might be due to OCrelated effects on affective judgements or memory for emotional stimuli. Previous studies on sex differences in emotional processing have rarely examined continuous gender (e.g., masculinity) or OC-related sources of variation. In this lab-based study, OC users, free-cycling women (i.e., nonusers), and men rated the emotional valence and intensity of emotional stimuli across three sensory modalities (e.g., visual, auditory, olfactory) to assess their immediate perception, evaluation, and memory for the stimuli. Differences in ratings were examined as a function of sex, masculinity, and OC use. In terms of emotional memory, OC users recalled more positive and less negative information than nonusers (i.e., relatively more positive than negative words, fewer negative objects and negative words). In terms of valence ratings, OC users and nonusers differed in their overall perception of stimuli, but the direction was stimulus-specific. Compared to non-users, OC users were more likely to perceive odours as positive and words as negative, and more likely to perceive negative facial expressions and negative words as negative. In terms of affective intensity ratings, OC users evaluated stimuli overall as more intense than nonusers, with this group effect being driven by olfactory intensity ratings. There was no evidence that gender (i.e., self-reported masculinity or measured voice pitch) explained a significant amount of variance in women’s affective valence or intensity ratings of stimuli, although women’s voice pitch was positively correlated with their olfactory intensity ratings. The OC-related emotional memory effect, stimulus-specific valence bias, and enhanced affective intensity bias are discussed in relation to findings from previous studies examining hormonal factors in emotional processing.