In this video excerpt from a 2025 Therapy First webinar, DR. JULIA MASON discusses brain maturation during adolescence.
Dr. Julia Mason is a board-certified pediatrician and Fellow of the American Academy of Pediatrics. She is a graduate of the University of Illinois (MS in Nutritional Science, MD). She completed residency training in Pediatrics at Children’s Hospital Los Angeles.
Brain development in adolescence
Adolescence represents the second most intensive period of brain maturation after early childhood, with full prefrontal cortex development often extending into the mid-20s (and beyond age 30 in neurodiverse individuals).
Sex hormones play a role in synaptic pruning, myelination, and maturation of executive function, emotional regulation, and social cognition.
The limbic system matures earlier than the prefrontal cortex, resulting in heightened emotional volatility, novelty-seeking, and sensitivity to social rejection. Meanwhile, impulse control and the ability to evaluate long-term consequences remain underdeveloped.
This raises important questions regarding young people and their capacity for informed consent to irreversible medical intervention.
ADHD and autism spectrum conditions
ADHD and autism spectrum conditions delay prefrontal maturation by years, and impair typical adolescent gains in executive function, social cognition, and emotional recognition.
Up to 25% of ADHD youth and 50–70% of autistic youth present with co-morbid conditions, which are likely to increase their vulnerability to identity-related distress.
In today’s cultural landscape, some neurodivergent youth appear to approach gender identity as an explanation for experiences of social struggle and emotional pain. While this can provide a sense of belonging and meaning, it also raises concerns about whether complex developmental needs are being simplified solely through an identity-based lens, with other issues being sidelined and unaddressed.
Evidence and the gender affirming medical treatment
Dr. Mason discusses registry data from Finland, which demonstrate that:
Psychiatric comorbidities persist despite gender affirming medical treatment
Suicide risk appears to track with the broader mental health challenges present in this population, rather than showing clear reduction following medical transition.
Dr Mason notes that major US pediatric guidelines are not based on systematic reviews of evidence that would support the prescription of puberty blockers and cross-sex hormones to minors (although some professionals have been calling for this since 2018).
Follow Up
Clinicians can join Therapy First for an annual membership fee of just $50. You’ll access monthly clinical case conferences, a supportive online community, a library of previous webinars and early access to events - learn more here.
If you’re a parent, request a referral for a therapist here.
