From her page:
QuoteWhen we take into account that all perinatal males experience defeminization of the brain (Wallen and Baum (2002), thereby leaving them incapable of female behavior and sensibility, by testosterone that is converted to estradiol by a process of aromatase, it is not too hard to imagine, that for some reason, yet to become clear to science, that that process could easily have been disrupted leading to incomplete masculinization of some male brains.
This is what happens in rodents, not human beings! In humans and other primates, brain masculinization and defeminization appears to be entirely driven through androgen receptors, with estrogen receptors playing no significant role. So there's a major problem with her theory already.
Unfortunately, most of the research that's been done into sexually dimorphic brain development has used rats and mice, in which aromatization and estradiol play the main role in driving male brain development. However, that's something that appears to be specific to rodents. It doesn't apply in humans anyway, as is shown by a condition called Complete Androgen Insensitivity Syndrome (CAIS), which produces people who are genetically male, but both look and behave just like ordinary, genetically female women. This is despite their aromatase enzyme and estradiol receptors being completely unaffected by the mutation. The rodent equivalent of CAIS is a mutation called Tfm, and it produces mice and rats with a female appearance, but whose behaviour is predominantly male (which shows that there is quite a big species difference there!).
In fact, there's plenty of evidence that MTF transsexuality is due to incomplete masculinization of the brain, either through some kind of genetic condition that reduces testosterone production (e.g. XXY karyotype), or through being prenatally exposed to drugs or chemicals with testosterone-suppressing properties (e.g. DES). It's though there being insufficient testosterone present though, not anything to do with aromatase or estradiol.
QuoteIt is well known that large doses of exogenous estrogens administered to some genetic males, dramatically reduces the anxiety of gender dysphoria. The same outcome is true when gender dysphoric genetic females take testosterone. (i.e. Testosterone increases-->Estrogen decreases = feelings of well being).
This is exactly what you'd expect to happen if trans people have actually undergone cross sex brain development. If you have a female brain, then it's going to be expecting female-typical hormone levels to be present, and it shouldn't be surprising that it doesn't function very well with male-typical hormone levels instead.
