Simón(e) Sun studies how gonadal hormones contribute to sex-variable neurobiology, with the broad goal of improving sex- and gender-related mental healthcare. The steroid hormones –  progesterone, androgens, and estrogens – shape the expression of different sex variable social behaviors such as aggression, mating, and parenting. These behaviors emerge during adolescence, but the mechanisms that direct these hormone-mediated effects are poorly understood. To reveal these mechanisms, Sun is investigating adolescent development in mice at three levels: genomics, neurophysiology, and neurocircuitry.