Facial expression of positive and negative emotions in patients with unipolar depression.

Neuropsychological research in major depression has generally been limited to the realm of cognition. This study focuses instead on the neuropsychology of affect. Emotional facial expression was examined in light of its presumed right cerebral hemisphere mediation and evidence for right hemisphere disorganization in major depression. Posed facial emotional expressions of four emotions were elicited and dynamically photographed in 30 unipolar depressives and 30 normal controls. Accuracy and emotional intensity of the expressions were rated by blind raters. Depressed patients were significantly impaired in the production of emotional facial expressions, particularly for positive ones. Several alternative explanations for the findings are discussed and further studies recommended.