Recognition of Facial Emotion Expressions in Patients with Depressive Disorders: A Prospective, Observational Study

Processing of emotional stimuli is altered in patients with depression. The present feasibility study investigated the features of emotional information recognition in people with depressive disorders and how these differ from individuals without depression to determine whether response times could potentially be used as a diagnostic marker to identify individuals at high risk of depression and as an indicator of antidepressant medication response.

The study recruited 32 individuals, 16 with single or recurrent depressive episodes and 16 control subjects without depression. Patients with depression received 8 weeks of antidepressant therapy. The severity of depressive symptoms at baseline and their changes on prescribed therapy were assessed using the Montgomery-Åsberg Depression Rating Scale (MADRS). The processing of emotional information was assessed using the computerized Penn Emotion Recognition Task (ER-40).

The two groups were well matched in terms of age and gender. There was no difference between the groups in their ability to correctly recognize happy or sad emotional facial expressions, but the average time patients with depression took to recognize a happy face was significantly longer than controls. In addition, they were more likely to misinterpret facial expressions as non-emotional. In patients with depression, the mean MADRS total score decreased from 26.3 ± 4.4 at baseline to 11.1 ± 8.9 at 8 weeks, a reduction of 57.8%. The proportion of responders with greater than 50% reduction in their baseline MADRS total score was 64.3%. Antidepressive treatment was associated with a reduction in the mean time required for recognition of a happy face (P < 0.05).

Patients with depression are slower to identify positive emotions but have a similar time to recognition of negative emotions as patients without depression. The greater time required for recognition of happiness distinguished the patients with depression from control subjects, and was also the only parameter that showed an improvement with antidepressant therapy, suggesting a specific relationship of this parameter with the depressive state.