Cerebral lateralization and gender differences in dichotic audiovisual asynchrony perception

Abstract

Both behavioral and neuroimaging studies on temporal processing have found a left cerebral hemisphere advantage for amodal auditory and visual stimuli. The current study investigated if this left hemisphere advantage also occurs for bimodal audiovisual asynchrony perception and possible gender differences in lateralization and temporal processing. To investigate this, 30 women and 30 men were tested using an audiovisual simultaneity judgment task with a binocular visual and dichotic auditory presentation. Results from the current study indicate that audiovisual synchrony perception has a left hemisphere advantage which is most evident in men. The results also revealed that men perceived more incidents of asynchrony in audiovisual speech, than women. The gender differences are concluded to most likely be due to a spatiotemporal advantage in men compared to women, maybe because of increased lateralization in men. Both the right ear advantage and the gender differences are most apparent when the video precedes the audio than vice versa, probably because the hemisphere receiving the second of the two inputs is more decisive when making the temporal judgment than the hemisphere receiving the first input. The findings show that gender differences might contribute to the large individual differences found in synchrony research and adds to a growing body of research giving insight into lateralization and gender differences in temporal perception and multisensory integration.