Swaab D F, Hofman M A
Netherlands Institute for Brain Research, Amsterdam.
Brain Res Dev Brain Res. 1988 Dec 1;44(2):314-8. doi: 10.1016/0165-3806(88)90231-3.
Sexual differentiation of the hypothalamus of the human brain is generally believed to take place around midpregnancy and thought to be related to the development of sexual orientation and gender identity. The present life span study on the human sexually dimorphic nucleus (SDN) of more than a hundred subjects revealed, however, that at the age of 2-4 years the SDN cell number reaches a peak value, and that only after this age sexual differentiation becomes manifest. Furthermore, the SDN cell number in homosexual men was not different from that of the male reference group, but significantly larger than the cell number in age-matched women.
一般认为，人类大脑下丘脑的性别分化大约发生在妊娠中期，并且被认为与性取向和性别认同的发展有关。然而，目前对一百多名受试者的人类性二态核（SDN）的寿命研究表明，在2至4岁时，SDN细胞数量达到峰值，并且只有在这个年龄之后性别分化才会显现出来。此外，同性恋男性的SDN细胞数量与男性参照组没有差异，但明显多于年龄匹配的女性的细胞数量。
