Impact of hypomanic personality traits on brain functional connectivity during a dynamic theory-of-mind task

Hypomanic personality traits are present in the general population and represent a risk factor for developing bipolar disorder. This personality style, notably its social component, is linked to difficulties in theory of mind (i.e., ability to infer mental states). Exploring the neural correlates of mental states' inference in individuals with these personality traits can provide meaningful insights into the development of bipolar disorder. The aim of the present study was therefore to investigate the potential impact of hypomanic traits on brain activation and task-based connectivity strength during a dynamic theory of mind task in a nonclinical population. A total of 52 nonclinical participants were recruited, and hypomanic traits were assessed with the Hypomanic Personality Scale. The severity of hypomanic traits was positively associated with right middle and inferior frontal gyri activations (in high vs. low inference in nonemotional condition and emotion vs. no emotion in high inference, respectively). It was also associated with stronger connectivity between the salience network (i.e., bilateral putamen and pallidum) and bilateral superior temporal gyri (high inference in nonemotional condition), and between cerebellar and temporal areas (high inference in emotional condition). These changes may either reflect adaptations or differential processing, and further studies are therefore mandatory.