Trait anger modulates neural activity in the fronto-parietal attention network

Abstract

Anger is considered a unique high-arousal and approach-related negative emotion. The influence of individual differences in trait anger on the processing of visual stimuli is relevant to questions about emotional processing and remains to be explored. Using functional magnetic resonance imaging (fMRI), we explored the neural responses to standardized images, selected based on valence and arousal ratings in a group of men with high trait anger compared to those with normative to low anger scores (controls). Results show increased activation in the left-lateralized ventral fronto-parietal attention network to unpleasant images by individuals with high trait anger. There was also a group by arousal interaction in the left thalamus/pulvinar such that individuals with high trait anger had increased pulvinar activation to the high-arousal (versus low arousal) unpleasant images as compared to controls. Thus, individual differences in trait anger in men are associated with brain regions subserving executive attentional and sensory integration during the processing of unpleasant emotional stimuli, particularly to high arousal images.

Fig 1. Brain response to unpleasant images.

(A) Main effect of group (HTAs > controls) for unpleasant images across arousal conditions. The HTAs exhibited increased activations within the left IFG/precentral gyrus, MFG, insula, and IPL compared with the control group when viewing unpleasant images. (B) A significant group × arousal interaction for unpleasant images emerged in the left thalamus (pulvinar) driven by the difference in brain response for arousal (high>low) within the HTAs [open bars; t(19) = 3.20, p = 0.003]. In the control group, no difference in the brain response to unpleasant images [diagonal filled bars; t(16) = -0.62, p = 0.54] emerged. Whole-brain significance threshold was set to p < 0.005, combined with a minimum cluster-extent of 26 contiguous voxels (702 mm³), to yield a corrected cluster-level false positive rate of p < 0.05. IFG = inferior frontal gyrus, MFG = middle frontal gyrus, IPL = inferior parietal lobule. Red bars indicate unpleasant high-arousal images; white bars indicate unpleasant low-arousal images. ** p < 0.01.