Functional connectivity of resting-state attention network in first-episode treatment-naive depressed patients

Abstract

Objective To observe the functional connectivity of attentional network in first-episode treatment-naive depressed patients with resting-state functional MR imaging (rfMRI), and to investigate the neuropathologic mechanism of attention dysfunction. Methods Eighteen first-episode treatment-naive depressed patients were collected in our hospital from August 2015 to March 2017, and 16 healthy controls matched with age, gender and education were chosen at the same time period. All subjects accepted rfMRI. Pearson correlation analysis was performed on all the time series values of the two regions of interest (ROIs), and their correlation coefficient was obtained. Fisher z transformation was performed to reflect the functional connection strength of the two ROIs through z scores. Results As compared with healthy controls, depressed patients showed abnormal enhancement on functional connectivity of the attentional network in the left anterior cingulate and supplementary motor area (z scores: 0.21±0.10 vs. 0.13±0.09, P=0.029), right basal ganglia region and dorsolateral prefrontal cortex (z scores: 0.18±0.12 vs. 0.10±0.08, P=0.048), right frontal eye field and intraparietal suleus (z scores: 0.19±0.12 vs. 0.10±0.05, P=0.006), right frontal eye field and nucleus ceruleus (z scores: 0.18±0.13 vs. 0.09±0.07, P=0.018). Conclusion Abnormal functional connectivity of attentional network exists extensively in first-episode treatment-naive depressed patients, which may be due to attention impairment in depressed patients. Key words: Depression; Attentional network; Resting state; Functional magnetic resonance imaging; Functional connectivity