Individuals change their evaluations of human faces depending on the valence of the stimuli presented with the faces. The present study investigated whether repeatedly presenting picture stimuli in pairs would evoke various emotions that would influence the subjects’ preferences for and impressions of facial stimuli. The subjects’ preferences for the facial stimuli did not differ consistently between before and after the facial stimuli were presented in tandem with emotional pictures. The direction of the change differed depending on the sex of the participant and the sex of face stimulus, even when the face was paired with a picture of the same valence. The emotional pictures appeared to have an effect on the emotions experienced in response to the face stimuli: the male participants, who were likely to feel pleasant emotions toward the pleasant pictures, were also likely to feel positive emotions toward the face stimuli paired with those pictures. Moreover, the female participants, who were likely to feel unpleasant emotions toward the unpleasant pictures, were also likely to feel afraid of the male faces paired with those pictures. These results suggest that the ability of an emotional stimulus to affect our preferences for and impressions of a face stimulus, as well as the degree of this effect, are highly sensitive to factors such as the sex of the participant and the sex of facial stimulus.
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