Brain networks sub-serving self-referential processing in depression

Abstract

Introduction

Persistent pondering over negative self-related thoughts is a central feature of depressive psychopathology.

Objectives

In the present study, we sought to investigate the neural correlates of abnormal negative self-referential processing (SRP) in patients with major depressive disorder (MDD) and its impact on subsequent cognitive control-related neuronal activation.

Aims

We hypothesized aberrant activation dynamics during the period of negative and neutral SRP in the rostral anterior cingulate cortex (rACC) and in the amygdala in patients with MDD. We assumed abnormal activation in the fronto-cingulate network during Stroop task execution.

Methods

Nineteen depressed patients and 20 healthy controls participated in the study. Using an event-related fMRI design, negative, positive and neutral self-referential statements were displayed for 6.5s and followed by incongruent or congruent Stroop conditions.

Results

In contrast to controls, patients did not exhibit valence-dependent rACC activation differences during SRP. A novel finding was the significant activation of the amygdala and the reward-processing network during presentation of neutral self-referential stimuli relative to baseline and to affective stimuli in patients. The fMRI analysis of the Stroop task revealed a reduced BOLD activation in the right frontoparietal network of patients in the incongruent condition after negative SRP only.

Conclusions

Thus, the inflexible activation in the rACC may correspond to the inability of depressed patients to shift their attention away from negative self-related stimuli. The accompanying negative affect and task-irrelevant emotional processing may compete for neuronal resources with cognitive control processes and lead thereby to deficient cognitive performance associated with decreased frontoparietal activation.

Disclosure of interest

The authors have not supplied their declaration of competing interest.