Relationship between regional homogeneity of male depressed patients and the severity of depression: a resting-state fMRI study
Objective 
To explore the regional homogeneity (ReHo) feature of the spontaneous neural activity within young male depressed patients, and conduct correlation analysis of the abnormal regions with the severity of depressive symptoms. 
 
 
Methods 
19 male depressed patients and 19 educated age-matched male healthy controls were undergone resting-state functional magnetic resonance imaging scanning at 3.0 Tesla. The whole brain’s regional homogeneity was calculated. The ReHo values of abnormal brain regions after alphasim correction were conducted correlation analysis with the total score of Hamilton Rating Scale for Depression. 
 
 
Results 
As compared with the controls, the depressed patients exhibited significantly increased ReHo in the bilateral parahippocampal (-30, -42, -9: K=43: 27, -33, -12: K=18) and the right posterior cingulate gyrus(3, 15, 33: K=54), while decreased ReHo in the right postcentral gyrus (27, -36, 54, K=21) (P<0.05, Alphasim). The correlation analysis showed that the ReHo of the right parahippocampal gyrus was positively correlated with the HAMD17 total scores (r=0.535, P=0.018). 
 
 
Conclusions 
The male depressed patients exhibit abnormities in the limbic-related brain regions during rest, and the extent of damage is correlated with the severity of depression. 
 
 
Key words: 
Depressive disorder; Gender; Resting-state; ReHo; Severity of depression