Outgroup emotion processing in the vACC is modulated by childhood trauma and CACNA1C risk variant

Abstract

A high frequency of outgroup contact-as experienced by urban dwellers and migrants-possibly increases schizophrenia risk. This risk might be further amplified by genetic and environmental risk factors, such as the A-allele of rs1006737 within the calcium voltage-gated channel subunit alpha1 C gene and childhood interpersonal trauma (CIT). Both have been related to ventral anterior cingulate cortex (vACC) functioning. We investigated vACC functioning, during ingroup and outgroup emotion perception in relation to rs1006737 and CIT. Group membership was manipulated through a minimal group paradigm. Thus, in our functional magnetic resonance imaging study, a group of healthy Caucasian participants (n = 178) viewed video-recorded facial emotions (happy vs angry) of actors artificially assigned to represent the ingroup or the outgroup. Rs1006737 and CIT were related to brain activation for group and emotion specific processing. The group-emotion interaction in the vACC showed reduced sensitivity to emotional valence for outgroup member processing. Specifically for the angry outgroup condition, we found a gene by environment interaction in vACC activity. We speculate that the increased schizophrenia risk in migrants and urban dwellers could therefore be facilitated via this pathophysiological pathway.

Fig. 1.

Interaction of Emotion and Group. The interaction of group (ingroup vs outgroup) and emotion (happy vs angry) factors in the ACC ROI is driven by differences in emotional ingroup processing. PSC = percent signal change. Sex was equally distributed among the ingroup and outgroup and all actors depicted all facial expressions.

Fig. 2.

Interaction of rs1006737 and childhood trauma with emotion and group. At the condition level, there is significant interaction between rs1006737 and trauma, particularly for processing angry outgroup emotions. T = childhood trauma; NT = no childhood trauma; GG or GA/AA of rs1006737 (A=risk allele); PSC = percent signal change. Sex was equally distributed among the ingroup and outgroup and all actors depicted all facial expressions.