Gender Identity, Brain sex and Transsexualism: a guide for the gender skeptics
In this post I’ll explain the scientific basis for some of the terminology applied to transsexualism and why the medical establishment understands it as a legitimate medical condition. It’ll be a rebuttal of some common complaints and I’ll post all my sources at the end of the post. Feel free to ask me anything or @ me if you have any questions or curiosities on the topic.
Common Complaint: Gender Identity isn’t real or Gender Identity is the same as feeling uncomfortable with Gender Roles.
First of all, what is the clinical definition (that is, the definition used in manuals and guidelines for diagnosing and treating Transsexualism) of Gender Identity and where did it even came from?
The Standards of Care, published by the WPATH, defines Gender Identity (sometimes called “Experienced Gender”) this way:
“A person’s intrinsic sense of being male (a boy or a man), female (a girl or a woman) […]”
That sounds incredibly vague, doesn’t it? One could ask which definition of “gender” is being used in the guidelines. Well, the DSM-V has this to say on the matter of gender:
“The need to introduce the term gender arose with the realization that for individuals with conflicting or ambiguous biological indicators of sex (i.e., “intersex”), the lived role in society and/or the identification as male or female could not be uniformly associated with or predicted from the biological indicators and, later, that some individuals develop an identity as female or male at variance with their uniform set of classical biological indicators. […]”
So the clinical perception of gender as being distinct from biological sex was originated as a way of explaining the experiences of transgender intersex people, that is, intersex people who were brought up as male or female depending of the “sex” they were assigned at birth and during adulthood or adolescence ended up living socially as the opposite “sex”.
On the 1968 Paper, “Can a Biological Force Contribute to Gender Identity?”, Howard J. Baker and Robert J. Stoller (a pioneer on the study of transsexualism) described the experiences of six intersex individuals who despite having no visible atypical anatomy and being raised as typical members of their assigned sex, persistently affirmed that they belonged to the opposite sex. Upon puberty, all of them developed anatomical changes corresponding to the sex that they declared to belong to.
The paper describes the concept of Gender Identity and its development on this way:
Stoller recognized a similarity between the intersex individuals described in his paper and the experiences of transsexual individuals (who have existed at least since the 1930s ):
On the late 2000s we get the following definition on the DSM-V:
“Thus, gender is used to denote the public (and usually legally recognized) lived role as boy or girl, man or woman, but, in contrast to certain social constructionist theories, biological factors are seen as contributing, in interaction with social and psychological factors, to gender development.”
You may have noticed that both definitions assert that gender identity is created by a collection of factors including the awareness of one’s anatomy (a marker of biological sex), family up-bring (the social reinforcement of gender roles) and some unknown (at least in 1968) biological force. You may also have noticed that Stoller’s description of gender identity makes a contrast between the belief of being male or female and the sense of being masculine or feminine.
1) The clinical concept of Gender Identity isn’t synonymous with Gender Roles (the social expectation of masculinity and femininity). Gender Identity is a collection of social (gender roles), biological (visible sex differences) and psychological factors (the unknown factor as described in 1968).
2) The clinical concept of Gender Identity has existed for over forty years. Tumblr didn’t invent it.
On a 1982 paper called “The Theory of Gender Identity Disorders”, written by Jon K. Meyer, the standard process for gender identity development is described on this way:
The paper goes on describing how this standard gender development is atypical in the case of transsexual individuals. To those individuals whose gender identity is discrepant to biological sex, the psychological conflict alongside social repression of the biologically incongruent gender identity leads to noticeable distress, social impairment and disturbance of one’s body image. You may have noticed that these descriptions are quite similar to our modern diagnosis criteria for Gender Dysphoria.
Common Complaint: There’s no scientific evidence of gender identity.
Several neuroimaging studies were made to understand the role of hormonal influence in brain tissue during hormonal sensitivity periods (prenatal and pubertal periods) on humans. The literature on the effects of prenatal androgen exposure is strong and it’s based on the studies about intersex individuals with different degrees of androgen exposure.
Because anatomical sexual dimorphism happens before the sexual differentiation of the brain (and before the development of gender identity), it’s assumed that transsexual people have some brain-limited condition where there is no concordance between the sexually differentiated state of the brain and the body.
There are several (including recent research made in 2015) studies that give credence to this theory. The studies compare the average brain phenotypes (or patterns) of non dysphoric male and female control groups with ftm and mtf control groups including the ones who hadn’t gone through hormonal replacement therapy at the time of the study and didn’t had intersex conditions.
A 2016 review of nearly all literature on neuroimaging studies on gender dysphoric people, came to the following conclusion:
“A difference in brain phenotype of people with GI [Gender Incongruence] compared to natal sex controls in various brain measures suggests a sex-atypical development of the brain. […] Although the number of studies examining the brain of people with GI is still low, they have taught us that brain phenotypes for FtM and MtF seem to exist, and provided evidence for the role of prenatal organization of the brain in the development of gender incongruence.”
Common Complaint: Ftms don’t have “male brains” and Mtfs don’t have “female brains”.
…That’s not a completely inaccurate affirmation actually. Another 2016 review of transgender neuroimaging studies says the following:
“Untreated MtFs and FtMs who have an early onset of their gender dysphoria and are sexually oriented to persons of their natal sex show a distinctive brain morphology, reflecting a brain phenotype. These phenotypes are different from those of heterosexual males or females; the differences affect the right hemisphere and cortical structures underlying body perception.”
The results from neuroimaging studies don’t actually say that Ftms have “male brains” or that Mtfs have “female brains”. This is an oversimplification of the results from neuroscience. While the studies did show several similarities between the brain patterns of men and Ftms and women and Mtfs; the overall conclusion was that Ftms and Mtfs have unique brain phenotypes that are different than the brain phenotypes found in non dysphoric men and women.
Early onset dysphoric Ftms have a more “masculinized” brain structure and early onset dysphoric Mtfs have a more “feminized” brain structure but the overall “package” looks unique enough to be counted as a distinct phenotype on itself. It would be more accurate to say that that Ftms have Ftms’ brains and that Mtfs have Mtfs’ brains.
The brain phenotypes of early onset and late onset dysphoric people are significantly different. This is in agreement with old theories on the differences between early and late onset dysphoria. Early onset Ftms are often gynephiles (attracted to women) while early onset Mtfs are often androphiles (attracted to men). Their dysphoria manifests in early childhood, increases during puberty and persists through adulthood.
Late onset dysphoric people also have unique brain phenotypes but their phenotypes are distinct than the ones presented by the early onset group. It’s also worth noting that neither the early nor the late onset group share the same brain phenotype of homosexual men and women.
Common Complaint: Gender Dysphoria is the same as Body Dismorphia.
It’s indeed possible for someone to have both Gender Dysphoria and Body dismorphia disorder and some neurological studies have found a link between the brain areas responsible for body perception (it’s all on the right hemisphere) and sense of self and the areas that are sex atypical in transgender individuals (mainly on the right hemisphere). Does that means that dysphoria is just another form of body dismorphia? No.
Body dismorphia involves a disconnection from physical reality and is often associated with symptoms of OCD and eating disorders. Usually, a person with this disorder desires the removal of a body part because they see it as being deformed.
Dysphoric people are usually self aware enough to understand that their bodies are not physically deformed and their dissatisfaction is consistently focused on specific gendered body parts. Upon undergoing gender transition procedures, this psychological distress in dissipated.
These notable differences between dismorphia and dysphoria were visible even on the early years of psychoanalytic research on transsexualism:
Common Complaint: Brain sex is a myth, neuroimaging is completely flawed and brain sex research is sexist.
Humans, just like all mammals, have sexually dimorphic bodies and these sexually dimorphic bodies will be influenced by a fundamental organ such as the brain. The human brain itself is vulnerable to hormones involved on the development of sexually dimorphic structures. There’s nothing surprising nor controversial in affirming that the brain, just like any other organ, will exhibit signs of sexual differences.
Neuroimaging research has consistently shown the differences in size, white and gray matter patterns, and many other structures present in the brains of men and women. Usually, men are taller than women. The fact that some men are shorter doesn’t negate the fact that on average men are taller than women. Individual exceptions or overlaps don’t negate the existence of sexual dimorphism because sexual dimorphism is measured by averages rather than by individual distinctions.
The misuse and mischaracterization of neuroimaging research by media outlets doesn’t invalidate the entire scientific field of neuroimaging. If someone has been using a distorted interpretation of neurological research to excuse sexism then the burden of the blame is on them rather than being placed on an entire scientific field.
Common Complaint: But Gina Rippon/Daphna Joel/Rebecca Jordan-Young/Cordelia Fine said that brain sex is a myth.
1) Daphna Joel’s research was methodologically wrong. Her research classified brain phenotypes as “male” or “female” based on the phenotypes exhibited by the 30% extreme examples of gender differences between men and women. If an individual exhibited a single overlapping characteristic they were immediately placed on the “substantial variable” group. If your entire classification method relies on unrealistic examples of sexual dimorphism then you’ll easily arrive at the conclusion that neurological dimophism isn’t internally consistent.
In other words, if your premise is fundamentally wrong (classifying sexual dimorphism based on extreme individual examples rather than averages) your results will be skewed.
This 2015 rebuttal of Joel’s research says the following:
“The definition of“internal consistency”Joel et al. use is so extreme that, in realistic conditions, it can only generate results consistent with their hypothesis. Under more realistic assumptions, the method of Joel et al. virtually always returned the same pattern of results—a preponderance of “substantially variable” profiles, a minority of “intermediate profiles,” and a very small proportion (often close to zero) of “sex-typical” profiles.”
This 2016 rebuttal of Joel’s research says the following:
“The failure of the brain to meet these two requirements does not mean that “human brains cannot be categorized into two distinct classes: male brain/female brain.” In fact, an individual’s biological sex can be classified with extremely high accuracy by considering the brain mosaic as a whole.”
Another 2016 rebuttal concludes with the following:
“A simple multivariate analysis using the same data suggests quite the opposite: Brains are indeed typically male or typically female.”
2) Gina Rippon, Cordelia Fine and Jordan Young have made a career criticizing supposedly methodological flaws on neuroimaging studies while consistently citing and defending the results of Joel’s research as being a more accurate model for understanding brain phenotypes.
It’s not unrealistic to affirm that they might be biased towards a particular type of result, given the fact that they have been consistently involved in controversies within the neuroscientific community because of their habit of coining inflammatory terms such as “neurotrash”, “neurononsense” and “neurosexism” to label neuroimaging research whose results differ with the “mosaic brain” belief.
Common Complaint: The belief in brain sex and gender identity is biological essentialism.
Recognizing that biological differences exist between males and females doesn’t necessarily imply that men are better than women. The average men can be taller and stronger but we do know that women are just as capable of engaging in physically taxing activities regardless of this biological difference.
While there are some studies that show differences in brain function or language acquisition, for example, neuroscientists are still aware of the role of environmental influence on brain development. The recent popularity of the field of epigenetics and the concept of brain plasticity are proofs of this awareness.
While some transgender people do express their gender identity in a somewhat stereotypical way, research on the development of gender identity has shown that it isn’t necessarily limited by gender roles. Again, having an inner sense of being male or female doesn’t imply that one is following all of the expectations of “masculinity” and “femininity”.
Moreover, while some of the diagnosis tools (questionnaires and so on) and the diagnosis of dysphoria in children are very reliant on display or lack of display of traditional “masculinity” and “femininity”, professionals on the field are still instructed to explore things deeper than surface level presentation of masculinity or femininity.
“Assessment of gender dysphoria and mental health should explore the nature and characteristics of a child’s or adolescent’s gender identity. A psychodiagnostic and psychiatric assessment—covering the areas of emotional functioning, peer and other social relationships, and intellectual functioning/school achievement—should be performed.
Assessment should include an evaluation of the strengths and weaknesses of family functioning. Emotional and behavioral problems are relatively common, and unresolved issues in a child’s or youth’s environment may be present.”
(from the Standards of Care)
(2012) Standards of Care for the Health of Transsexual, Transgender, and Gender-Nonconforming People, Version 7, International Journal of
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American Psychiatric Association: Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition. Arlington, VA, American Psychiatric Association, 2013.
Baker H, Stoller R: Can a biological force influence gender identity .Amer J Psychiat 124:1653-1658, 1968.
Stoller, R. J. (1968). Sex and gender: Vol. 1. The development of
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Gardiner, J. K. (2013). Masculinity’s Interior: Men, Transmen, and Theories of Masculinity. The Journal of Men’s Studies, 21(2), 112–126. https://doi.org/10.3149/jms.2102.112
Byne W, Karasic DH, Coleman E, Eyler AE, Kidd JD,Meyer-Bahlburg HFL, Pleak RR, Pula J (2018) Gender dysphoria in adults: an overview and primer for psychiatrists, Transgender Health3:1, 57–73, DOI: 10.1089/trgh.2017.0053.
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