Reduced Medial Prefrontal-Subcortical Connectivity in Dysphoria: Granger Causality Analyses of Rapid Functional Magnetic Resonan

A cortico-limbic network consisting of the amygdala, medial prefrontal cortex (mPFC), and ventral striatum (vSTR) has been associated with altered function in emotional disorders. Here we used rapidly sampled functional magnetic resonance imaging and Granger causality analyses to assess the directional connectivity between these brain structures in a sample of healthy and age-matched participants endorsing moderate to severe depressive symptomatology as they viewed a series of natural scene stimuli varying systematically in pleasantness and arousal. Specifically during pleasant scene perception, dysphoric participants showed reduced activity in mPFC and vSTR, relative to healthy participants. In contrast, amygdala activity was enhanced to pleasant as well as unpleasant arousing scenes in both participant groups. Granger causality estimates of influence between mPFC and vSTR were significantly reduced in dysphoric relative to control participants during all picture contents. These �...

• Type: Journal
• Year: 2015
• Where: BRAIN
• Authors: Dean Sabatinelli, Lisa M. McTeague, Mukesh Dhamala, David W. Frank, Timothy J. Wanger, Bhim Mani Adhikari
• Keywords: BRAIN 2015, Information Technology