Neural processing of emotional faces requires attention

TLDR

Attention gates early visual processing, yet evidence suggests emotional stimuli may activate brain regions automatically, independent of attention. The study aimed to determine whether emotional facial expressions elicit brain responses only when attention is available. Using fMRI, researchers measured activation to fearful, happy, and neutral faces and then assessed how a high‑load competing task modulated these responses. All regions, including the amygdala, responded to emotional faces only when attentional resources were sufficient, indicating that facial expression processing is under top‑down control.

Abstract

Attention gates the processing of stimuli relatively early in visual cortex. Yet, existing data suggest that emotional stimuli activate brain regions automatically, largely immune from attentional control. To resolve this puzzle, we used functional magnetic resonance imaging to first measure activation in regions that responded differentially to faces with emotional expressions (fearful and happy) compared with neutral faces. We then measured the modulation of these responses by attention, using a competing task with a high attentional load. Contrary to the prevailing view, all brain regions responding differentially to emotional faces, including the amygdala, did so only when sufficient attentional resources were available to process the faces. Thus, the processing of facial expression appears to be under top-down control.