Aberrant default mode network homogeneity in patients with first-episode treatment-naive melancholic depression

- The Default Mode Network Homogeneity (NH) of melancholic depression was first explored.
- First-Episode Treatment-Naïve patients with melancholic depression were recruited.
- Low NH in the right middle temporal gyrus and temporal pole was revealed in patients.
- The NH of right MTG/TP could be an important clue for identifying the physiopathology of MDD.

BackgroundMelancholic depression is a relatively homogenous subtype of major depressive disorders (MDD). The condition has several endogenous symptoms and represents strong biological components. However, its specific neurobiological mechanisms remain unknown. Previous neuroimaging findings indicated that default mode network (DMN) is closely related to MDD. The present study examined the network homogeneity (NH) of the DMN in patients with melancholic MDD.MethodsA total of 33 first-episode, treatment-naive melancholic MDD patients and 32 healthy controls underwent a resting-state functional magnetic resonance imaging scan. The data were analyzed using the NH method.ResultsCompared with healthy controls, patients with melancholic MDD showed low NH values in the right middle temporal gyrus and temporal pole (MTG/TP). The abnormal NH of this region and clinical characteristics were not correlated.ConclusionAbnormal NH pattern of DMN exists in patients with melancholic MDD. This feature may be part of the pathophysiological basis of this disorder.