Working memory (WM) theoretically affords the ability to privilege social threats and opportunities over other more mundane information, but few experiments have sought support for this contention. Using a functional logic, we predicted that threatening faces are likely to elicit encoding benefits in WM. Critically, however, threat depends on both the capacities and inclinations of the potential aggressor and the possible responses available to the perceiver. Two experiments demonstrate that participants more efficiently scan memory for angry facial expressions, but only when the faces also bear other cues that are heuristically associated with threat: masculinity in Study 1 and outgroup status in Study 2. Moreover, male participants showed robust speed and accuracy benefits, whereas female participants showed somewhat weaker effects, and only when threat was clearly expressed. Overall results indicate that working memory for faces depends on the accessibility of self-protective goals and on the functional relevance of other social attributes of the face.

Rapid identification of facial expressions can profoundly affect social interactions, yet most research to date has focused on static rather than dynamic expressions. In four experiments, we show that when a non-expressive face becomes expressive, happiness is detected more rapidly anger. When the change occurs peripheral to the focus of attention, however, dynamic anger is better detected when it appears in the left visual field (LVF), whereas dynamic happiness is better detected in the right visual field (RVF), consistent with hemispheric differences in the processing of approach- and avoidance-relevant stimuli. The central advantage for happiness is nevertheless the more robust effect, persisting even when information of either high or low spatial frequency is eliminated. Indeed, a survey of past research on the visual search for emotional expressions finds better support for a happiness detection advantage, and the explanation may lie in the coevolution of the signal and the receiver.

Detecting signs that someone is a member of a hostile outgroup can depend on very subtle cues. How do ecology-relevant motivational states affect such detections? This research investigated the detection of briefly-presented enemy (versus friend) insignias after participants were primed to be self-protective or revenge-minded. Despite being told to ignore the objectively nondiagnostic cues of ethnicity (Arab vs. Western/European), gender, and facial expressions of the targets, both priming manipulations enhanced biases to see Arab males as enemies. They also reduced the ability to detect ingroup enemies, even when these faces displayed angry expressions. These motivations had very different effects on accuracy, however, with self-protection enhancing overall accuracy and revenge-mindedness reducing it. These methods demonstrate the importance of considering how signal detection tasks that occur in motivationally-charged environments depart from results obtained in conventionally motivationally-inert laboratory settings.