Specific alterations of anterior cingulate cortex subregions in somatic depression: A resting-state fMRI study

To investigate the changes in resting-state functional connectivity (rs-FC) of different anterior cingulate cortex (ACC) subregions in patients with somatic depression (SD), and its correlation with clinical characteristics.

We recruited 38 patients with SD, 33 patients with non-somatic depression (NSD), and 30 healthy controls (HC).All subjects underwent resting-state functional magnetic resonance imaging(rs-fMRI).The ACC subregions (pregenual ACC(pgACC), subgenual ACC(sgACC), and supracallosal ACC(supACC)) were used as regions of interest to make functional connections with the whole brain.Using correlation analysis to explore the relationship between rs-FC values and the severity of clinical symptoms.

SD group showed decreased rs-FC between the right pgACC and the left superior temporal gyrus (STG)/ left middle temporal gyrus (MTG) (MNI: x = -45, y = -12, z = -9, t = 4.36/MNI: x = -48, y = -33, z = -3, t = 3.89, AlphaSim correction, voxel-level P < 0.001, cluster-level P < 0.05), and rs-FC was negatively correlated with Somatic subscale (SS) (r = -0.572, P < 0.0001). But there was no significant correlation with Depression Subscale (DS) (P > 0.05).

The group of SD exhibit functional alterations in the right pgACC and left STG/left MTG, which may be the neuroimaging basis for the occurrence of SD.

The functional abnormality between the ACC subregions and temporal lobe show a new neural circuit for SD patients and provide a theoretical basis for further clinical intervention.