Whether we are defined as a male or female is an important part of our identity. For most but not all people, their gender identity and physical characteristics match. For those people that do not match, their identity is referred to as trans-identity or transsexual.
In a new study, brain researcher Georg Kanz of the University Clinic for Psychiatry and Psychotherapy of the MedUni Vienna has found that gender identity of each human is present in the links between brain regions, reports Science Daily.
For the study, the researchers compared 23 female-to-male and 21 male-to-female transsexuals with female and male control participants using magnetic resonance tomography (MRT) imaging.
The researchers found significant differences in the structure of the brain connections between male and female control participants.
They also found that the transsexual participant's brain connections were different than the male and female control participants.
The researchers discovered a strong correlation between the structural connections in the brain networks with the testosterone levels measured in blood plasma.
The research demonstrates that gender cannot always be identified by physical appearance.
Gender identity can also be influenced by biological sex, sex hormones and sexual orientation.
If gender is established by the psyche, the brain is responsible for human thoughts and feelings which provide a neural representation of gender identity.
"These results suggest that the gender identity is reflected in the structure of brain networks which form under the modulating influence of sex hormones in the course of the development of the nervous system," said Rupert Lanzenberger of the University Clinic for Psychiatry and Psychotherapy of the MedUni Vienna.
The study was conducted by the Dutch Institute for Neurosciences in Amsterdam with cooperation between clinics of the MedUni Vienna.