Fear extinction to an out-group face: the role of target gender.

Conditioning studies on humans and other primates show that fear responses acquired toward danger-relevant stimuli, such as snakes, resist extinction, whereas responses toward danger-irrelevant stimuli, such as birds, are more readily extinguished. Similar evolved biases may extend to human groups, as recent research demonstrates that a conditioned fear response to faces of persons of a social out-group resists extinction, whereas fear toward a social in-group is more readily extinguished. Here, we provide an important extension to previous work by demonstrating that this fear-extinction bias occurs solely when the exemplars are male. These results underscore the importance of considering how gender of the target stimulus affects psychological and physiological responses to out-group threat.