Citation

Varkevisser T, Gladwin TE, Heesink L, van Honk J, Geuze E. Soc. Cogn. Affect. Neurosci. 2017; 12(12): 1881-1889.

Affiliation

Research Center Military Mental Health Care, Utrecht, The Netherlands.

Copyright

(Copyright © 2017, Oxford University Press)

DOI

10.1093/scan/nsx113

PMID

29040723

Abstract

Impulsive aggression is common amongst military personnel after deployment, and may arise because of impaired top-down regulation of the amgydala by prefrontal regions. This study sought to further explore this hypothesis via resting-state functional connectivity analyses in impulsively aggressive combat veterans. Male combat veterans with (n = 28) and without (n = 30) impulsive aggression problems underwent resting-state fMRI. Functional connectivity analyses were conducted with the following seed-regions: basolateral amygdala (BLA), centromedial amygdala (CeM), anterior cingulate cortex (ACC), and anterior insular cortex (AIC). Regions-of-interest analyses focused on the orbitofrontal cortex and periaqueductal gray, and yielded no significant results. In exploratory cluster analyses, we observed reduced functional connectivity between the (bilateral) BLA and left dorsolateral prefrontal cortex (DLPFC) in the impulsive aggression group, relative to combat controls. This finding indicates that combat-related impulsive aggression may be marked by weakened functional connectivity between the amygdala and prefrontal regions, already in the absence of explicit emotional stimuli. Group-differences in functional connectivity were also observed between the (bilateral) ACC and left cuneus, which may be related to heightened vigilance to potentially threatening visual cues, as well as between the left AIC and right temporal pole, possibly related to negative memory association in impulsive aggression.

© The Author (2017). Published by Oxford University Press.

Language: en

Keywords

DLPFC; amygdala; functional connectivity; impulsive aggression; neuroimaging