Perceptual expertise has an emotional side: holistic face processing is modulated by observers' emotional state

Faces are typically processed holistically, in that features and their relations are integrated into a perceptual unit rather than being processed independently. However, in certain cases -; such as for other-race faces -; holistic processing is diminished (Tanaka, Kiefer, & Bukach, 2004). Notably, positive emotional states have been shown to improve recognition performance for other-race faces (Johnson & Fredrickson, 2005), raising the possibility that such effects are driven by an increase in holistic processing. In the current experiment, we directly tested whether an observer's emotional state impacts holistic processing. Participants were randomly assigned to an emotion induction condition, in which a positive, negative, or neutral emotional state was elicited through the viewing of a short film clip (e.g., from a comedy routine, horror movie, or instructional video). The degree to which faces were processed holistically was assessed both before and after the emotion induction, using a composite task that required participants to make same/different judgments about a cued part (either the top or bottom) of sequentially presented chimeric faces. This task indexes holistic processing by measuring the degree to which performance is impacted by the task-irrelevant face halves. Results revealed that holistic processing was significantly modulated by induced emotional state: participants in the negative emotion condition exhibited decreased holistic processing, whereas participants in the positive emotion condition exhibited an increase. A manipulation check confirmed that participants in the positive and negative emotion induction conditions reported mood changes in the expected directions. These findings suggest that an observer's emotional state can affect the degree to which stimuli are processed holistically. Furthermore, given that a shift to a more holistic processing strategy has been linked with the development of perceptual expertise, these results raise the possibility that the positive emotions typically associated with objects of expertise contribute to this change in processing strategy.