Neural basis of emotion recognition deficits in first-episode major depression.

BACKGROUND: Depressed individuals demonstrate a poorer ability to recognize the emotions of others, which could contribute to difficulties in interpersonal behaviour. This emotion recognition deficit appears related to the depressive state and is particularly pronounced when emotions are labelled semantically. Here, we investigated its neural basis by comparing emotion recognition processing between depressed, recovered and healthy individuals.
METHOD: Medication-naive patients with a first major depressive episode, medication-free patients who had recovered from a first episode, and a group of matched healthy individuals participated. They were requested to identify the emotion of angry and fearful face stimuli, either by matching them to other emotional faces on a perceptual basis or by matching them to a semantic label, while their brain activity was measured with functional magnetic resonance imaging.
RESULTS: The depressed individuals performed worse than recovered and healthy individuals on the emotion-labelling but not the emotion-matching task. The labelling deficit was related to increased recruitment of the right amygdala, left inferior frontal gyrus and anterior cingulate cortex.
CONCLUSIONS: Deficits in semantic labelling of negative emotions are related to increased activation in specific brain regions and these abnormalities are mood state-dependent. These results indicate that accessing semantic knowledge about negative information triggers increased amygdala and left inferior frontal gyrus processing, which subsequently impairs task-relevant behaviour. We propose that this may reflect the activation of negative schemas.