Many teens struggle with their mental health. In fact, more U.S. adolescents are reporting mental illness than ever. But transgender youth face an especially high risk of anxiety and depression. Seeing trans friends deal with these challenges inspired Charlotte Rosario, 18, to study brain development and mental health in trans youth.

Charlotte joined a lab at Stanford University in California. The team has been following a group of young people as they grow up. Some are transgender. Others are non-trans, or cisgender. Charlotte looked at brain scans and mental-health surveys from 20 trans and 23 cis participants. The data had been collected in early puberty.

As other research has shown, trans kids reported greater anxiety and depression. Their brain scans also showed structural differences in regions like the thalamus. This area plays a role in regulating mood. For instance, trans boys with larger thalamus regions showed higher levels of depression. This suggests a possible link between gender identity and brain regions linked to mental health, Charlotte says.

She hopes her findings might shed light on the unique challenges faced by young trans people. She also hopes it will inspire further research aimed at providing inclusive health care for people of all gender identities.

Charlotte is currently a senior at the Nueva School in San Mateo, Calif. Her research earned her a finalist spot in the 2025 Regeneron Science Talent Search. (That competition is run by Society for Science, which also publishes Science News Explores). In this interview, Charlotte shares her research experiences and advice.  

What inspired this project?

“What really drew me to that lab and wanting to get involved in the research was my own personal story. In middle school, I actually lost a family member to suicide. And that was a really challenging time for me,” Charlotte says. “Over the years, I’ve learned to heal and come to terms with everything that’s happened by trying to better understand the mechanisms of mental health from a scientific standpoint.”

What was your favorite part of this project?

“The data processing was actually quite interesting. A lot of people would say, ‘Oh, cleaning data, that sounds so menial and boring,’” Charlotte says. “But I think when it comes to working with neuroimaging … it would hit me at certain times like, ‘I am looking at a literal kid, who is probably my age and, who knows, might be dealing with a lot of issues. And I’m looking at their brain.’” That experience, she says, can be “really intimate.”

What’s next for you?

“I really do hope to keep continuing to do this research,” Charlotte says. She’s keen to analyze data collected from the participants when they were older. Here, she had been looking at data from when the trans kids were just starting gender-affirming hormone therapy. (This treatment helps trans kids go through puberty changes that match their gender identity.)

“I’m sure we’ll probably find some interesting results when we look at the end of hormone treatment,” Charlotte says. “That will really help us get at that big question of, what really is the impact of gender-affirming hormone therapy.”

Any advice for research newbies?

“Don’t be afraid to just fall down rabbit holes,” Charlotte says. “And try to look inward if you don’t really know what you’re curious about in the external world.” She notes that “what really drew me into this research was my own personal story and identity. And that actually ended up moving my focus again toward the outside world and to other people.”