Our social evaluation of other people is influenced by their faces and their voices. How?

Audiovisual Integration in Social Evaluation. By Mila Mileva et al.
Journal of Experimental Psychology: Human Perception and Performance, in press
http://eprints.whiterose.ac.uk/116201/1/MTWB_Audioviusual_author_version.pdf

Abstract: Our social evaluation of other people is influenced by their faces and their voices. However, rather little is known about how these channels combine in forming “first impressions.” Over 5 experiments, we investigate the relative contributions of facial and vocal information for social judgments: dominance and trustworthiness. The experiments manipulate each of these sources of information within-person, combining faces and voices giving rise to different social attributions. We report that vocal pitch is a reliable source of information for judgments of dominance (Study 1), but not trustworthiness (Study 4). Faces and voices make reliable, but independent, contributions to social evaluation. However, voices have the larger influence in judgments of dominance (Study 2), whereas faces have the larger influence in judgments of trustworthiness (Study 5). The independent contribution of the 2 sources appears to be mandatory, as instructions to ignore 1 channel do not eliminate its influence (Study 3). Our results show that information contained in both the face and the voice contributes to first impression formation. This combination is, to some degree, outside conscious control, and the weighting of channel contribution varies according the trait being perceived.

Keywords: First  impressions; social evaluation; audio-visual integration; faces; voices