Hypothalamus volume in men: Investigating associations with paternal status, self-reported caregiving beliefs and adult attachment style

Abstract

Most studies on mammalian attachment and caregiving have focused on the mother-child relationship, particularly in humans. Yet, recent re-considerations of attachment theory and changing societal roles of male caregivers have highlighted the necessity for research with fathers. In this pre-registered study (https://aspredicted.org/5uj5y.pdf), we examined the structure of the hypothalamus, an important subcortical brain area for attachment and caregiving behavior, in a sample of N=95 fathering (child age 5-6 years) and non-fathering men. While we found no difference in hypothalamus volume between fathers and non-fathers, fathers' caregiving style was related to interindividual variation in hypothalamus volume. Specifically, we observed that fathers who held greater belief in the importance of their role as a father and reported more enjoyment of interacting with their child had greater total hypothalamus volume. This finding suggests that there is individual variability in the association between brain structure and caregiving style in fathers, warranting further research.