Sexual Differentiation of the Human Brain in Relation to Gender-Identity, Sexual Orientation, and Neuropsychiatric Disorders

Reference work entry


During the intrauterine period, a testosterone surge in boys masculinizes the fetal brain, whereas the absence of such a surge in girls results in a feminine brain. Since sexual differentiation of the genitals takes place much earlier in intrauterine life than sexual differentiation of the human brain, these two processes can be influenced independently of each other. Gender identity (the conviction of belonging to the male or female gender), sexual orientation (hetero-, homo-, or bisexuality), pedophilia, and the risks for neuropsychiatric disorders are programmed into our brain during early development. There is no proof that postnatal social environment has any crucial effect on gender identity or sexual orientation. We discuss the relationships between structural and functional sex differences of various brain areas and the way they change along with changes in the supply of sex hormones on the one hand and sex differences in behavior in health and disease on the other.


Androgen Receptor Sexual Orientation Gender Identity Congenital Adrenal Hyperplasia Sexual Differentiation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



Androgen receptor


Central nucleus of the human bed nucleus of the stria terminalis




Complete androgen insensitivity syndrome


Congenital adrenal hyperplasia


Estrogen receptor


Female-to-male transsexual person


Intermediate nucleus


Interstitial nucleus of the anterior hypothalamus


Male-to-female transsexual person


Suprachiasmatic nucleus


Sexually dimorphic nucleus of the preoptic area


Supraoptic nucleus



We thank Mrs. W.T.P. Verweij for correcting the English. Dr. A-M Bao is supported by Nature Science Foundation of China (30970928), Science Foundation of Chinese University, and China Exchange Programme of the Royal Netherlands Academy of Arts and Sciences (KNAW) (project 09CDP011).

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Copyright information

© Springer Science+Business Media, LLC 2013

Authors and Affiliations

  1. 1.Netherlands Institute for NeuroscienceAmsterdamThe Netherlands
  2. 2.Department of NeurobiologyZhejiang University School of Medicine, Key Laboratory of Medical Neurobiology of Ministry of Health of ChinaZhejiang, HangzhouChina

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