Sex differences in resting-state hypothalamic connectivity and its relationship with negative emotion and behavior measures in young adults.

The hypothalamus plays a crucial role in motivated behavior, including those driven by negative emotions. Men and women are known to differ in individual traits and behaviors in relation to production and regulation of negative emotion. However, whether or how sex differences in hypothalamic functional connectivities and these individual behavioral traits are related remains unclear. We curated the Human Connectome Project - Young Adults dataset and compared hypothalamic resting state functional connectivities (rsFC) and negative emotions, as evaluated by the Achenbach Adult Self-Report, of 406 men and 464 women. Imaging data were processed with published routines and evaluated with a corrected threshold. We examined the relationship between hypothalamic rsFC and negative emotions traits with linear regression and explored sex differences by slope test. Men relative to women showed higher rule-breaking, aggression, anti-social, but lower anxiety scores. In two-sample T test with age and drinking severity as covariates, men showed higher hypothalamic rsFC with lateral orbitofrontal cortex, cerebellum, superior frontal cortex and intra-occipital sulcus, and women showed higher rsFC in the left fusiform gyrus, parahippocampal gyrus, superior parietal gyrus and precuneus. The connectivity markers of sex differences were also differentially associated with individual rule-breaking, aggression, anti-social and anxiety scores between men and women, as confirmed by slope tests. Men and women exhibited significant differences in hypothalamic rsFC as well as the inter-relationship between the rsFC and self-reported negative emotion and behavior measures. These findings suggest potential sex differences in the neural circuits of emotion processing.