The neuroanatomy of homosexuality

The anterior hypothalamus of the human brain is sexually dimorphic and has been investigated for dimorphism with regards to sexual orientation through examination of postmortem brains of homosexual males, heterosexual males, and heterosexual females. Studies examining the interstitial nuclei of the anterior hypothalamus3 and the anterior commisure have shown correlation to sexually-orientated dimorphism. Through further research, a relationship between the development of these sexually dimorphic regions and steroid hormone levels has been established. Though neither consequence nor causation can be definitively demonstrated from this research, its implications are suggestive of the early differentiation of human sexual orientation and its origins spanning neurobiology and endocrinology.