Sex differences in the functional asymmetry for facial affect perception.

Twenty-six right-hand-dominant women and 26 right-hand-dominant men were required to identify the facial affective expression of Ekman and Friesen's (1978) angry, happy, and neutral stimuli using a forced-choice reaction-time paradigm with only angry or happy alternatives signified by the respective response manipulanda. Stimuli were presented within the left or right visual fields to provide additional data on sex differences in the lateralized processing of facial affective stimuli. The results supported the hypothesis of greater laterality among men with equivalent response times for women and men to stimuli within the right but not the left visual fields. Men were significantly faster in processing affective facial information within the left visual field. The results also indicated that differential rates of learning occur in affective tachistoscope tasks for happy and angry stimuli. Thus, opposite conclusions may be derived from procedural differences among studies in the number of identification trials employed.