NEURAL PROCESSING OF EMOTIONAL MUSIC AND SOUNDS IN DEPRESSION

Abstract

The present study uses functional MRI and an emotional sound and music paradigm to examine how neural processing of emotionally provocative auditory stimuli is altered in depression. Functional MRI was used to localize the neural response to auditory emotional stimulation, hypothesized to differ between depressed and never-depressed control participants in brain regions known to be involved in reward processing and rumination. Twenty individuals with depression (MDD) and 18 controls (ND) listened to positive and negative emotional musical and nonmusical stimuli during fMRI scanning, and gave subjective ratings of valence and arousal following scanning. ND participants exhibited greater activation to positive versus negative stimuli in the ventral anterior cingulate cortex (vACC), dorsal amygdala, and hippocampus, regions known to be affected in depression. They also showed two distinct processing networks for music versus sounds, with music activating the default mode network (DMN) and sounds activating object identification regions to a greater extent. When compared with control participants, depressed participants showed a different pattern of activation to these emotional stimuli in the ACC. In the rostral part of the ACC, ND participants showed greater activation for positive information, while MDD participants showed greater activation to negative information. In the dorsal and perigenual ACC, the pattern of activation distinguished between the types of sounds, with ND showing greater activation to music compared to sounds, while MDD showed greater activation to sounds, with the greatest response to negative sounds. The anterior cingulate is critical for emotion processing and functions as a relay for diverting cognitive control to demanding tasks. These results suggest that the type of auditory stimulation, as well as the emotional content may be processed differently by people with depression.