Increased neural responses to negative facial emotions and their relationship with dysfunctional attitudes among unmedicated individuals with major depressive disorder

Despite increasing knowledge about the brain mechanisms underlying major depressive disorder (MDD), efforts to explore the neural underpinnings of emotional processing among individuals with MDD and their relationship with neural abnormalities and the maintenance of depression, are still ongoing. This exploratory fMRI study examined the nature of neural responses to emotional faces and their relationship with dysfunctional attitudes among unmedicated individuals with MDD. Twenty-five unmedicated individuals with MDD and 23 control participants completed a facial emotion perception task and self-report questionnaires, including the Beck Depression Inventory-II (BDI-II) and the Dysfunctional Attitude Scale (DAS). Participants with MDD (vs. control participants) showed less accuracy in identifying mildly (50%) and intensely (100%) happy, and mildly (50%) sad faces. Whole-brain analyses reflected increased activation in bilateral inferior frontal gyrus, left posterior (in response to 50% and 100% sad vs. neutral faces) left anterior (in response to 50% sad vs. neutral faces), right anterior, and right middle cingulate cortices (in response to 100% sad vs. neutral faces) among participants with MDD. No group differences were observed in neural responses to happy faces. Hyperactivity in the left inferior frontal gyrus during negative emotion perception was correlated with the DAS’ Performance Evaluation scores in the MDD group. This study highlighted that hyperactivity in the inferior frontal gyrus during negative facial emotion processing is associated with dysfunctional attitudes among people with MDD. The findings warrant further fMRI research to yield neural evidence for cognitive models of depression.