Brain Structure Variances in Transgender Individuals

Brain Structural Distinctions found among Transgender Individuals

In a groundbreaking study supported by the São Paulo Research Foundation and published in the journal Scientific Reports, researchers at the University of São Paulo's Medical School (FM-USP) have delved into the brain structure of transgender individuals. The study, which utilised magnetic resonance imaging (MRI), marks a significant step forward in a new and largely unexplored research field.

Brazil has emerged as a pioneer in this area, with few studies having focused on the brain structure of transgender people. The study's first author, Giancarlo Spizzirri, revealed that they found transgender individuals have characteristics that align with the gender they identify with, and their brains exhibit particularities.

The study found variations in the volume of the brain region called the insula in both hemispheres for both groups of transgender women, regardless of hormone use. Interestingly, the size of the insula was reduced in transgender women compared to cisgender women, but not smaller than in cisgender men.

Professor Geraldo Busatto, an associate researcher in the study, emphasised the relevance of this discovery. Transgender individuals often face issues related to their perception of their own body due to not identifying with the sex assigned at birth and suffering discrimination and persecution. The detection of a difference in the insula, a region that plays a key role in body image, self-awareness, autonomic control, homeostatic information, and visceral sensations, is significant in this context.

The insula is a region with multiple elements, and the authors hypothesised that this finding might be a characteristic of transgender women. It's worth noting that brain structures vary greatly among individuals, and reduced gray matter volume in a brain region does not necessarily mean fewer nerve cells.

The study involved 80 individuals aged 18 to 49 years old, divided into four groups: cisgender women, cisgender men, transgender women who had never used hormones, and transgender women who had used hormones for at least a year. Another conclusion of the study was that this particular feature could not be explained by hormone treatment.

Carmita Abdo, coordinator of the Sexuality Research Program (ProSex) at the Psychiatry Institute of Hospital das Clínicas and principal investigator of the study, reiterated that the findings show that being transgender "doesn't just refer to different kinds of behavior that people develop." Abdo also stated that the evidence is building up that it's not a matter of ideology, and their own research based on MRI scans points to a detectable structural basis.

The researchers plan to conduct more studies, with a key interest in determining the stage of development in which differences occur. It would be interesting to study brain scans of children and young adults with transgender characteristics and compare them with the scans of adult trans women.

The Federal Board of Medicine in Brazil has had guidelines on how to work with the needs of transgender individuals in clinical and surgical practice since 1997. The study is expected to stimulate interest in research on the brain structure of transgender people, contributing to a better understanding and more informed care for this community.

However, it's important to note that there's no such thing as a typically female or male brain. This study adds to the growing body of evidence that challenges the notion of binary brain structures and reinforces the complexity and individuality of the human brain.