While magnetic resonance imaging (MRI) has been used to study sex differences by observing the structure of the brain, the morphology has rarely been explored in transgender women (i.e. assigned male at birth) diagnosed with gender dysphoria.
In a recent study, researchers from the Medical School of the University of São Paulo, Brazil, decided to investigate this by recruiting 80 participants between the ages of 18 and 49 years. They were categorized into four groups of 20 members each: cisgender women, cisgender men, transgender women who had never used hormones, and transgender women who had used hormones for at least a year. MRI scans were then used to look for differences in gray and white matter volume of the brains.
It was revealed that both groups of transgender women had variations in the volume of the insula in both hemispheres. The insula is a region of the brain that reads the physiological state of the body, thus being responsible for body image and self-awareness.