Research in the Sisk Lab is directed toward understanding the neural, endocrine, and behavioral changes that take place during puberty and adolescence. Adult cognition, social behaviors, responses to sensory stimuli, and responses to environmental stressors are remarkably different from those of the juvenile organism. Thus, the juvenile-to-adult transition is a fundamental period of neural development. Some recent work in the Sisk lab has focused on structural changes in the hamster amygdala during adolescence, and how this may be relevant for changes in the processing of sensory stimuli and their effects on behavior. Other projects focus on the role of steroid hormones in the neurogenesis and gliogenesis that occurs during adolescent brain development. This work has direct implications for human adolescent development and human mental health because a number of sex-biased psychopathologies (e.g., eating disorders, depression, and schizophrenia) emerge during adolescence. Furthermore, the influence of steroids on developmental processes in the human adolescent nervous system is altered or perturbed by a variety of circumstances, including the delay of gonadal development brought about by eating disorders, extreme exercise, or disease, the abuse of anabolic androgenic steroids, and exposure to environmental endocrine disruptors. The Sisk lab hopes to establish the temporal and developmental parameters within which steroid hormones impact nervous system during puberty in order to fully define and understand periods of vulnerability for the development of behavioral pathologies.