Functional integration of anterior insula related to meaning in life and loneliness

Abstract

Background: Meaning in life (MIL), defined as people's feelings of life's meaningfulness, plays a vital role in buffering loneliness - an important indicator of depression and other psychological disorders. Considerable evidence shows that MIL arises from widely distributed brain activity; however, how such activity is functionally integrated and how it influences loneliness is still understudied.

Methods: We here examined how the functional integration of brain regions is related to individual MIL based on resting-state functional magnetic resonance imaging data from the Human Connectome Project (N = 970).

Results: We found that the global brain connectivity (GBC) of the right anterior insula (rAI) can significantly predict individual MIL. Moreover, mediation analyses were conducted to investigate how the brain influences loneliness with MIL's mediation, which revealed that MIL fully mediates the effect of this hub on loneliness.

Conclusions: These findings suggest that the rAI is a key hub for MIL and loneliness. Its functional integration can be used as a biomarker to predict individual MIL and loneliness.

Keywords: Functional connectivity; Global brain connectivity; Loneliness; Meaning in life.