Here is a theory I have heard about the physical basis of transsexuality. I don’t know if there is any evidence for it, but it does not sound impossible.
There are differences between the brains of men and women; there are differences between the bodies of men and women. These are physical differences, resulting from differences in the physical development process. (Thus far is uncontentious.) Transsexuality is what happens when the brain develops according to one gender and the body develops according to the other. This is what produces the experience that transexuals describe as being of the opposite gender to their body.
“Our results show that the white matter microstructure pattern in untreated FtM transsexuals is closer to the pattern of subjects who share their gender identity (males) than those who share their biological sex (females). Our results provide evidence for an inherent difference in the brain structure of FtM transsexuals.”
“Our results show that the white matter microstructure pattern in untreated MtF transsexuals falls halfway between the pattern of male and female controls. The nature of these differences suggests that some fasciculi do not complete the masculinization process in MtF transsexuals during brain development.”
This web page speculates (based on no evidence) that the causal relation is the opposite: that such differences result from transsexuals’ preoccupation with being the opposite gender. Cf. the known differences in taxi drivers brains that may result from their years of navigation experience. The speculation leaves unexplained the origin of that preoccupation, and appears motivated by the author’s theory (which is what that web site is for) that sexual orientation is plastic.
Be all that as it may, there is a clear difference here between transsexuality and otherkin. The hypothesis in the last of these links, of voluntary (if unintended) self-modification, can apply to both. However, the involuntary developmental process suggested by the first two can only apply to transsexuality, since there is no developmental pathway for being an elf.
All FtM transsexuals selected [...] were erotically attracted to females
Right, so we don’t know whether the straight transmen were sorted with the straight cismen rather than the straight ciswomen because they have a male brain, or because they have a female-liking brain. We need to add homosexual controls.
Edit: I’m curious to what I’m being downvoted here for. I realize my comment didn’t add much to the discussion, but I simply wanted to express that my ideas were already generally here. Is it disapproval for that (to prevent a signal:noise ratio from being too small) or disapproval for something else?
Here is a theory I have heard about the physical basis of transsexuality. I don’t know if there is any evidence for it, but it does not sound impossible.
There are differences between the brains of men and women; there are differences between the bodies of men and women. These are physical differences, resulting from differences in the physical development process. (Thus far is uncontentious.) Transsexuality is what happens when the brain develops according to one gender and the body develops according to the other. This is what produces the experience that transexuals describe as being of the opposite gender to their body.
Some further references:
“White matter microstructure in female to male transsexuals before cross-sex hormonal treatment. A diffusion tensor imaging study” (Free.)
“Our results show that the white matter microstructure pattern in untreated FtM transsexuals is closer to the pattern of subjects who share their gender identity (males) than those who share their biological sex (females). Our results provide evidence for an inherent difference in the brain structure of FtM transsexuals.”
“The microstructure of white matter in male to female transsexuals before cross-sex hormonal treatment. A DTI study.” (Free.) This is by the same authors as the previous paper.
“Our results show that the white matter microstructure pattern in untreated MtF transsexuals falls halfway between the pattern of male and female controls. The nature of these differences suggests that some fasciculi do not complete the masculinization process in MtF transsexuals during brain development.”
This web page speculates (based on no evidence) that the causal relation is the opposite: that such differences result from transsexuals’ preoccupation with being the opposite gender. Cf. the known differences in taxi drivers brains that may result from their years of navigation experience. The speculation leaves unexplained the origin of that preoccupation, and appears motivated by the author’s theory (which is what that web site is for) that sexual orientation is plastic.
Be all that as it may, there is a clear difference here between transsexuality and otherkin. The hypothesis in the last of these links, of voluntary (if unintended) self-modification, can apply to both. However, the involuntary developmental process suggested by the first two can only apply to transsexuality, since there is no developmental pathway for being an elf.
Have we looked at whether those results on white matter structure discriminate male from female, and not female-liking from male-liking?
Both studies used heterosexual controls.
BTW, I found a legitimate free copy of the second paper and have updated the link.
Right, so we don’t know whether the straight transmen were sorted with the straight cismen rather than the straight ciswomen because they have a male brain, or because they have a female-liking brain. We need to add homosexual controls.
Voted up for shared intuitive theories.
Edit: I’m curious to what I’m being downvoted here for. I realize my comment didn’t add much to the discussion, but I simply wanted to express that my ideas were already generally here. Is it disapproval for that (to prevent a signal:noise ratio from being too small) or disapproval for something else?