This is part of a lecture given on May 5, 2010 by Prof. Robert Sapolsky at Stanford University. Prof. Sapolsky reviews studies he feels make a compelling case for those who assert that transsexualism is actually a type of intersex condition.
More on gender orientation
Those interested in gender roles and the brain should read Cordelia Fine’s Delusions of Gender. Fine does an excellent job at debunking pernicious myths while chronicling the history of the way neurology has been used to support gender roles. Having said that, trans readers may note that Fine someones conflates gender identity with gender role. Outside of this one critique, I strongly recommend the book to anyone who wants to look at the neurologic science behind gender role formation.