The face in the crowd effect unconfounded: happy faces, not angry faces, are more efficiently detected in single- and multiple-target visual search tasks.

Is it easier to detect angry or happy facial expressions in crowds of faces? The present studies used several variations of the visual search task to assess whether people selectively attend to expressive faces. Contrary to widely cited studies (e.g., Öhman, Lundqvist, & Esteves, 2001) that suggest angry faces "pop out" of crowds, our review of the literature found inconsistent evidence for the effect and suggested that low-level visual confounds could not be ruled out as the driving force behind the anger superiority effect. We then conducted 7 experiments, carefully designed to eliminate many of the confounding variables present in past demonstrations. These experiments showed no evidence that angry faces popped out of crowds or even that they were efficiently detected. These experiments instead revealed a search asymmetry favoring happy faces. Moreover, in contrast to most previous studies, the happiness superiority effect was shown to be robust even when obvious perceptual confounds--like the contrast of white exposed teeth that are typically displayed in smiling faces--were eliminated in the happy targets. Rather than attribute this effect to the existence of innate happiness detectors, we speculate that the human expression of happiness has evolved to be more visually discriminable because its communicative intent is less ambiguous than other facial expressions.