What Makes A Woman? Part 2: The Brain

Yesterday I wrote about the New York Times opinion “What Makes a Woman?” about diversity in the trans community, today I am writing about another comment the author made in the article.

Do women and men have different brains?
[…]
But when Bruce Jenner said much the same thing in an April interview with Diane Sawyer, he was lionized for his bravery, even for his progressivism.

“My brain is much more female than it is male,” he told her, explaining how he knew that he was transgender.
[…]
I have fought for many of my 68 years against efforts to put women — our brains, our hearts, our bodies, even our moods — into tidy boxes, to reduce us to hoary stereotypes. Suddenly, I find that many of the people I think of as being on my side — people who proudly call themselves progressive and fervently support the human need for self-determination — are buying into the notion that minor differences in male and female brains lead to major forks in the road and that some sort of gendered destiny is encoded in us.

That’s the kind of nonsense that was used to repress women for centuries. But the desire to support people like Ms. Jenner and their journey toward their truest selves has strangely and unwittingly brought it back.

Well actually Caitlyn is right and Ms. Burkett is wrong, there is a difference between women’s and men’s brain; transgender women’s brain is a lot like a women’s brain and  transgender men a lot like men’s brain.

There is substantial research to back that up. In Psychology Today article "Brain Differences Between Genders" by Gregory L. Jantz Ph.D., he writes,

Male brains utilize nearly seven times more gray matter for activity while female brains utilize nearly ten times more white matter. What does this mean?

Gray matter areas of the brain are localized. They are information- and action-processing centers in specific splotches in a specific area of the brain. This can translate to a kind of tunnel vision when they are doing something. Once they are deeply engaged in a task or game, they may not demonstrate much sensitivity to other people or their surroundings.

And there is also difference in the structure of the brain between genders…

A number of structural elements in the human brain differ between males and females. “Structural” refers to actual parts of the brain and the way they are built, including their size and/or mass.

Females often have a larger hippocampus, our human memory center. Females also often have a higher density of neural connections into the hippocampus. As a result, girls and women tend to input or absorb more sensorial and emotive information than males do. By “sensorial” we mean information to and from all five senses. If you note your observations over the next months of boys and girls and women and men, you will find that females tend to sense a lot more of what is going on around them throughout the day, and they retain that sensorial information more than men.

Additionally, before boys or girls are born, their brains developed with different hemispheric divisions of labor. The right and left hemispheres of the male and female brains are not set up exactly the same way. For instance, females tend to have verbal centers on both sides of the brain, while males tend to have verbal centers on only the left hemisphere. This is a significant difference. Girls tend to use more words when discussing or describing incidence, story, person, object, feeling, or place. Males not only have fewer verbal centers in general but also, often, have less connectivity between their word centers and their memories or feelings. When it comes to discussing feelings and emotions and senses together, girls tend to have an advantage, and they tend to have more interest in talking about these things.

White matter is the networking grid that connects the brain’s gray matter and other processing centers with one another. This profound brain-processing difference is probably one reason you may have noticed that girls tend to more quickly transition between tasks than boys do. The gray-white matter difference may explain why, in adulthood, females are great multi-taskers, while men excel in highly task-focused projects.

And the differences also carry over to the trans person. In the New Scientist article “Transsexual differences caught on brain scan” the author writes,

Antonio Guillamon's team at the National University of Distance Education in Madrid, Spain, think they have found a better way to spot a transsexual brain. In a study due to be published next month, the team ran MRI scans on the brains of 18 female-to-male transsexual people who'd had no treatment and compared them with those of 24 males and 19 females.

They found significant differences between male and female brains in four regions of white matter – and the female-to-male transsexual people had white matter in these regions that resembled a male brain (Journal of Psychiatric Research, DOI: 10.1016/j.jpsychires.2010.05.006). "It's the first time it has been shown that the brains of female-to-male transsexual people are masculinised," Guillamon says.

In a separate study, the team used the same technique to compare white matter in 18 male-to-female transsexual people with that in 19 males and 19 females. Surprisingly, in each transsexual person's brain the structure of the white matter in the four regions was halfway between that of the males and females (Journal of Psychiatric Research, DOI: 10.1016/j.jpsychires.2010.11.007). "Their brains are not completely masculinised and not completely feminised, but they still feel female," says Guillamon.

So Caitlyn is right when she says “My brain is much more female than it is male.”

No one knows why this is happens, just like no one knows why people are left handed but their brains are different from right handed people. Nature is diverse, lets celebrate that diversity.