Abnormal regional spontaneous neural activity in first-episode, treatment-naive patients with late-life depression: a resting-state fMRI study.

BACKGROUND

The previous resting perfusion or task-based studies have provided evidence of functional changes in the brains of patients with late-life depression (LLD). Little is known, so far, about the changes in the spontaneous brain activity in LLD during the resting state. The aim of this study was to investigate the spontaneous neural activity in first-episode, treatment-naive patients with LLD by using resting-state functional magnetic resonance imaging (fMRI).

METHODS

A novel analytical method, coherence-based regional homogeneity (Cohe-ReHo), was used to assess regional spontaneous neural activity during the resting state in 15 first-episode, treatment-naive patients with LLD and 15 age- and gender-matched healthy controls.

RESULTS

Compared to the healthy controls, the LLD group showed significantly decreased Cohe-ReHo in left caudate nucleus, right anterior cingulate gyrus, left dorsolateral prefrontal cortex, right angular gyrus, bilateral medial prefrontal cortex, and right precuneus, while significantly increased Cohe-ReHo in left cerebellum posterior lobe, left superior temporal gyrus, bilateral supplementary motor area, and right postcentral gyrus (p<0.005, corrected for multiple comparisons).

CONCLUSIONS

These findings indicated abnormal spontaneous neural activity was distributed extensively in first-episode, treatment-naive patients with LLD during the resting state. Our results might supply a novel way to look into the underlying pathophysiology mechanisms of patients with LLD.