Something in the way we move: Motion dynamics, not perceived sex, influence head movements in conversation.
Boker, Steven M.; Cohn, Jeffrey F.; Theobald, Barry-John; Matthews, Iain; Mangini, Michael; Spies, Jeffrey R.; Ambadar, Zara; Brick, Timothy R.
doi: 10.1037/a0021928
Journal of Experimental Psychology: Human Perception and Performance - Online First Publications & Volume 37, Issue 2
Abstract: During conversation, women tend to nod their heads more frequently and more vigorously than men. An individual speaking with a woman tends to nod his or her head more than when speaking with a man. Is this due to social expectation or due to coupled motion dynamics between the speakers? We present a novel methodology that allows us to randomly assign apparent identity during free conversation in a videoconference, thereby dissociating apparent sex from motion dynamics. The method uses motion-tracked synthesized avatars that are accepted by naive participants as being live video. We find that 1) motion dynamics affect head movements but that apparent sex does not; 2) judgments of sex are driven almost entirely by appearance; and 3) ratings of masculinity and femininity rely on a combination of both appearance and dynamics. Together, these findings are consistent with the hypothesis of separate perceptual streams for appearance and biological motion. In addition, our results are consistent with a view that head movements in conversation form a low level perception and action system that can operate independently from top–down social expectations. (PsycINFO Database Record (c) 2011 APA, all rights reserved)
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New Research: Something in the way we move: Motion dynamics, not perceived sex, influence head movements in conversation.