Hippocampus, amygdala, and insula activation in response to romantic relationship dissolution stimuli: A case-case-control fMRI study on emerging adult students

Abstract

Background: Romantic relationship dissolutions (RRDs) are associated with posttraumatic stress symptoms (PTSS). Functional magnetic resonance imaging in RRD studies indicate overlapping neural activation similar to posttraumatic stress disorder. These studies combine real and hypothetical rejection, and lack contextual information and control and/or comparison groups exposed to non-RRD or DSM-5 defined traumatic events.

Aim: We investigated blood oxygen level dependent (BOLD) activation in the hippocampus, amygdala, and insula of participants with RRDs compared with other traumatic or non-trauma stressors.

Methods: Emerging adults (mean age = 21.54 years; female = 74.7 %) who experienced an RRD (n = 36), DSM-5 defined trauma (physical and/or sexual assault: n = 15), or a non-RRD or DSM-5 stressor (n = 28) completed PTSS, depression, childhood trauma, lifetime trauma exposure, and attachment measures. We used a general and customised version of the International Affective Picture System to investigate responses to index-trauma-related stimuli. We used mixed linear models to assess between-group differences, and ANOVAs and Spearman's correlations to analyse factors associated with BOLD activation.

Results: BOLD activity increased between index-trauma stimuli as compared to neutral stimuli in the hippocampus and amygdala, with no significant difference between the DSM-5 Trauma and RRD groups. Childhood adversity, sexual orientation, and attachment style were associated with BOLD activation changes. Breakup characteristics (e.g., initiator status) were associated with increased BOLD activation in the hippocampus and amygdala, in the RRD group.

Conclusion: RRDs should be considered as potentially traumatic events. Breakup characteristics are risk factors for experiencing RRDs as traumatic.

Limitation: Future studies should consider more diverse representation across sex, ethnicity, and sexual orientation.

Keywords: Attachment; Emerging adult students; Physical assault; Posttraumatic stress; Sexual assault.