Reward and emotion influence attentional bias in rapid serial visual presentation.

Facial emotion constitutes an important source of information, and rapid processing of this information may bring adaptive advantages. Previous evidence suggests that emotional faces are sometimes prioritised for cognitive processing. Three experiments used an emotion-induced blindness task to examine whether this prioritisation occurs in a purely stimulus-driven fashion or whether it emerges only when the faces are task-relevant. Angry or neutral faces appeared as distractors in a rapid serial visual presentation sequence, shortly before a target that participants were required to identify. Either the emotion (Experiment 1) or gender (Experiments 2 and 3) of the distractor face indicated whether a correct/incorrect response to the target would produce reward/punishment, or not. The three experiments found that reward-related faces impaired subsequent target identification, replicating previous results. Target identification accuracy was also impaired following angry faces, compared with neutral faces, demonstrating an emotion-induced attentional bias. Importantly, this impairment was observed even when face emotion was entirely irrelevant to the participants' ongoing task (in Experiments 2 and 3), suggesting that rapid processing of the facial emotion might arise (at least in part) from the operation of relatively automatic cognitive-perceptual processes.