Mental health problems among adolescents remain a public health concern in the U.S. despite growing efforts to support mental wellbeing of youth. A part of the problem is a dearth of knowledge on evidence-based mechanisms on declining mental health in a particular subset of adolescents, and that subset is males and males on the autism spectrum. While studies on gender preponderance of mental health disorders contribute to the knowledge base on treating categorical psychopathology disorders sensitive to gendered issues, limitations include overlooking heterotypic comorbidities and understanding its underlying processes leading up to the development of mental health problems. Pubertal maturation is a process at which all adolescents transition through and for some adolescents, internalizing and externalizing symptoms may arise and can be overlooked. This is partly due to puberty viewed as a normative process for all adolescents going through “raging hormones,” a misconception of the role of hormones and behavior during development. Along with the social and physical changes that come with adolescent development, neurobiological activities are taking place implicating brain development and behaviors. Hormones play a role in adolescent development; however, their mechanistic impact, particularly in males, is less understood.

This dissertation had three specific aims. The first aim was to investigate the effect of pubertal maturation on internalizing and externalizing (I-E) symptoms in children and adolescent males across development. The second aim was to examine the role of puberty and autistic stereotypy on I-E symptoms in typically developing and autistic youths. The third aim was to test the effect of pubertal hormone testosterone, physical changes, and autistic stereotypy on depressive symptoms in typically developing and autistic adolescent males. Findings from this dissertation contribute to a small literature knowledge base on male adolescent development and psychopathology comorbidities.