Kerri Johnson and her team, builds on face research showing that people hold stereotyped beliefs about gender and emotion - seeing anger as a more male emotion and sadness as more female.
For example, a woman with an ambiguous facial expression is more likely to be judged as sad, whilst a man with an ambiguous expression is more often judged as angry. The problem with this line of investigation is that male faces, with thicker brows and square jaws, often do resemble a prototypical angry expression. So it's not entirely clear that people's biased interpretations of gender and facial emotion are based on gender stereotypes or if they're swayed by genuine sex differences in facial shape.
For the new research, Johnson and her colleagues videoed 14 male and 15 female actors throwing a ball into a bucket. Motion capture technology was used to create point light displays from these videos via markers placed on each actor's shoulder, elbow, wrist and hand. The actors read short paragraphs designed to stir different emotions in them before each throw - angry, neutral, happy or sad. The resulting stimuli simply showed the movement of the thrower's basic joints, seen as white dots against a black background.
A series of studies with dozens of undergrads confirmed that they were able to watch these basic point light displays and judge with some accuracy (up to 80 per cent in some conditions) the gender of the thrower and the emotion they were feeling. But crucially, there was a clear gender/emotion interaction, such that angry throwers were more likely to be judged male and sad throwers were more likely to be judged female. In fact, for angry female throwers, the ability to correctly discern their sex was reduced to no better than guessing, and the same for sad male throwers.
Further analysis and investigation confirmed that this confound existed because participants tended to rate angry throwers as more masculine (regardless of their actual sex) and sad throwers as more feminine.
An alternative, non-stereotype-based explanation for the results - that sad throwers and female throwers both throw with less velocity - was discounted. The male and female throwers in this study didn't differ in the velocity of their throws and the gender/emotion confound remained in place even after the point light displays were doctored to make all the emotions have the same velocity of throwing. 'The most likely explanation [for the findings],' the researchers said, 'is that emotions are gender stereotyped and thus affected sex perception via perceptions of masculinity/femininity.'
Johnson, K., McKay, L., and Pollick, F. (2011). He throws like a girl (but only when he’s sad): Emotion affects sex-decoding of biological motion displays. Cognition DOI: 10.1016/j.cognition.2011.01.016
This post was written by Christian Jarrett for the BPS Research Digest.