The functional connectivity of the right superior temporal gyrus is associated with psychological risk and resilience factors for suicidality

J Affect Disord. 2024 Apr 21:357:51-59. doi: 10.1016/j.jad.2024.04.048. Online ahead of print.

Abstract

Introduction: Suicide attempters show increased activation in the right superior temporal gyrus (rSTG). Here, we investigated the rSTG functional connectivity (FC) to identify a functional network involved in suicidality and its associations with psychological suicidality risk and resilience factors.

Methods: The resting state functional magnetic resonance imaging data of 151 healthy individuals from the Human Connectome Project Young Adult database were used to explore the FC of the rSTG with itself and with the rest of the brain. The correlation between the rSTG FC and loneliness and purpose in life scores was assessed with the NIH Toolbox. The effect of sex was also investigated.

Results: The rSTG had a positive FC with bilateral cortical and subcortical regions, including frontal, temporal, parietal, occipital, limbic, and cerebellar regions, and a negative FC with the medulla oblongata. The FC of the rSTG with itself and with the left central operculum were associated with loneliness scores. The within rSTG FC was also negatively correlated with purpose in life scores, although at a trend level. We did not find any effect of sex on FC and its associations with psychological factors.

Limitations: The cross-sectional design, the limited age range, and the lack of measures of suicidality limit the generalizability of our findings.

Conclusions: The rSTG functional network is associated with loneliness and purpose in life. Together with the existing literature on suicide, this supports the idea that the neural activity of rSTG may contribute to suicidality by modulating risk and resilience factors associated with suicidality.

Keywords: Loneliness; Meaning in life; Seed-based functional connectivity; Suicide risk; fMRI.