The interrelation of emotion regulation, anterior insula structure, and narcissistic traits

Emotion regulation deficits are prevalent in most psychiatric conditions; in particular in affective and personality disorders. The insula cortex is an intersection of emotion regulation, (expressive suppression vs. cognitive reappraisal), affective disorders, and traits predisposing dysfunctional personality. In this study, we tested the interrelation of emotion regulation strategies, brain structure, and narcissistic personality traits in a sub-clinical cohort.

In a sample of 172 psychiatrically healthy individuals we obtained 3 T MRI to acquire high resolution T1 weighted images for analyses of voxel- and surface-based structural parameters (SPM12/CAT12) along with measures of dispositional use of emotion regulation (Emotion Regulation Questionnaire; ERQ) and narcissistic traits (Pathological Narcissism Inventory; PNI). We tested their interrelation using a GLM approach and mediation models.

ERQ mediated the negative association of right insula volume and PNI and the association of right insula gyrification and PNI. PNI mediated the association of bilateral insula volume and ERQ. Additionally, PNI sub-scales were positively associated with gyrification of bilateral anterior insulae, cortical thickness of left precuneus and negatively correlated with cortical thickness of the left inferior temporal gyrus.

In contradistinction to preceding studies, no associations have been identified in prefrontal brain regions.

This is the first study that primarily tested meditated correlations of emotion regulation, brain structure, and narcissistic traits supporting the idea of the insula as a convergence structure for affective and personality disorders. Moreover, additional analyses indicate involvement of further brain regions such as precuneus and inferior temporal gyrus that have also been discussed in self-attributional processes.