Intermediate States of Sexuality: Intersexuality, Blended Sexual Identity, & Bisexuality

Bad Hair Days, who viewed my slideshow (see sidebar), posted this question on January 3rd on AE Brain's blog:

“What hit me with your slides was the ignorance on any in-between state according to sexual orientation and sexual identity (bisexuals, Kinsey scale, transgender, intergender).”

Hi Bad Hair,

Sorry about the long delay answering this excellent question. LIFE got in the way.

As explained in my presentation and as illustrated in my graph in Part 10 of the slideshow "Science & Sexuality," the data indicates that human sexuality is comprised of at least three dimensions or parameters: (1) body/genitalia, (2) sexual identity, and (3) sexual orientation. Each of these dimensions is a continuum from default state (typical female) to fully altered state (typical male). Intermediate states of alteration then are to be expected for each of these dimensions, resulting in: (1) intersex morphologies on the body dimension, (2) blended sexual identity on the sexual identity dimension, and (3) bisexuality on the sexual orientation dimension. Everyone is someplace on each of these three dimensions, and according to this theory, one’s sexuality could be plotted as a point in the three-dimensional space on the graph in Part 10. Persons who have undergone intermediate alteration in all three dimensions would have a sexuality represented by a point at the origin of all three coordinates putting them at the center of the graph. They would be people who have ambiguous genitalia (roughly a 3 on the Prader scale: http://www.aboutkidshealth.ca/HowTheBodyWorks/The-Prader-Scale.aspx?articleID=7715&categoryID=XS-nh4-03) , who feel both female and male, and who are attracted to both females and males (bisexual intersexuals with blended identity).

Just how much alteration an individual undergoes during fetal development is determined by a combination of genes and steroid hormone influence during the critical period of development for each of these three parameters. The critical periods for the three dimensions are different so the degree of alteration is usually different for each parameter, resulting in an individual occupying a different point on each continuum. Thus, since I am a CisLesbian, my genetics and fetal hormonal influence was such that I underwent largely default organization on the “body scale” and “identity scales” but much alteration on the “sexual orientation scale” producing my innate sexuality profile: female-bodied (“gynemorphic”), female identity (“gynecentric”), and attracted to females (“gynephilic”). I differ, then from typical females, who are attracted to males (“androphilic”) because typical females are near default state in every way.

The neurological studies looked only at brains of people who the researchers have reason to believe are at one or the other extreme of the sexual identity continuum or the sexual orientation continuum (for the sexual identity or sexual orientation research respectively). It is critical that the experimental subjects (the gay men, the transsexuals) are correctly identified as such so that a difference in the brain from controls (straight men, cissexuals) is more likely to be seen (if in fact brain differences account for these behavioral differences). The researchers knew the medical and life histories of their subjects (see original papers cited in my presentation) and I’m sure they purposely avoided subjects that would “muddy” the results in order to improve their chances of seeing a difference between experimental and control subjects. I would expect people with murky identities and bisexual orientation would have brain regions with intermediate organization (e.g., brain volume, neuron cell number) between default and fully altered states.

The prenatal hormonal theory causing “sexuality at birth” as championed by scientists such as Milton Diamond explains the infinite variety of sexualities manifested by human populations everywhere. Biologists recognize that normal populations are comprised of individuals – individuals are unique by definition. Everyone’s sexuality is unique and occupies its own spot in the three-dimensional sexuality space. I hope that this explanation answers your question.