Recognition of Facial Emotion Expressions in Patients with Depressive Disorders: A Functional MRI Study

Abstract

Background: The present study evaluated the cortical activation during emotional information recognition.

Methods: The study group included 16 patients with depression, and 16 healthy subjects were enrolled as a control group. Patients received eight weeks of antidepressant therapy. Functional MRI evaluated the cortical activation twice in the patient group and once in the control group. The fMRI task processed the emotional information with face demonstration from the PennCNP test battery.

Results: During the processing of emotional information, patients showed activation in the middle and the inferior frontal gyri, the fusiform gyrus, and the occipital cortex. After treatment, patients showed a significant decrease in the frontal cortex activation for negative face demonstration and no frontal activation for positive emotion recognition. The left superior temporal gyrus activation zone appeared in patients after treatment and in the control group. Healthy subjects showed more intense frontal cortex activation when processing neutral emotions and less when showing happy and sad faces. Activation zones in the amygdala and the insula and deactivation zones in the posterior cingulate cortex were revealed in the controls.

Conclusion: This study confirms the hypothesis that anomalies in the processing of emotional stimuli can be a sign of a depressive disorder.

Keywords: antidepressant therapy; depression; emotion recognition; functional MRI.

Figure 1

The fMRI paradigm design. The first rest period (indicated in green) was discarded to ensure reaching the T1 equilibrium. Six consecutive blocks were analysed. P+, demonstration of positive, happy faces; N, a task with neutral emotionless faces; N-, a task with negative, sad faces.

Figure 2

Activation of the frontal cortex in patients before (BT) (A–C), after (AT) (D–E) antidepressant therapy and in healthy controls (CG) (F–H) during facial emotion recognition. Demonstration of positive, happy faces (P+) (A,F), neutral emotionless faces (N) (B,D,G) and negative, sad faces (N-) (C,E,H). The corresponding difference image (I) showed a significant decrease of activation area in the right middle frontal gyrus for negative faces (p < 0.001).

Figure 3

Activation of the left fusiform gyrus (A,B) in patients before (BT) and after (AT) antidepressant therapy on demonstration of neutral faces (N). The corresponding difference image (C) showed a significant decrease of activation area in the left fusiform gyrus, BA37 for neutral faces (p < 0.001).

Figure 4

Activation of the left superior temporal gyrus in patients after therapy (AT) (A) and in healthy controls (CG) (B) on demonstration of negative faces (N-).

Figure 5

Activation of the left insula (A) on demonstration of positive faces (P+) and the left amygdala (B) on recognition of neutral emotions (N) in the control group (CG).

Figure 6

Deactivation zones in the cingulate cortex in the control group (CG), on the left, while processing negative (N-) and positive (P+) emotional information, and on the right, on demonstration of neutral faces (N).