WebMD, the internet portal to self-diagnosis for serious diseases everywhere, has a section called “How Male and Female Brains Differ,” that states, “Recent studies highlight a long-held suspicion about the brains of males and females. They’re not the same… Scientists now know that sex hormones begin to exert their influence during development of the fetus.”
Until the advent of the MRI, scientists and doctors have long believed that the male and female brain differ based on their chromosomal make-up, but a new study released on November 30, 2015, in the journal Proceedings of the National Academy of Sciences begs to differ and my end up shifting the paradigm on conventional perception regarding what makes people male and female.
Get ready to change your page WebMD because the study demonstrates that, “…although there are sex/gender differences in brain structure, brains do not fall into two classes, one typical of males and the other typical of females, nor are they aligned along a ‘male brain–female brain’ continuum,” eluding to the brain having a more mosaic feature than a binary function, a theory most of the general population believes in.
The first to examine sex differences in the brain concluding that brains do not fit into a definitive male/female variation, but that each brain is a veritable stew of both male and female [and everything in between] characteristics. The researched involved more than 1,400 MRI’s from multiple male and female brains primarily focusing on the section of the brain that is perceived as having the largest gender differences.
“These findings are corroborated by a similar analysis of personality traits, attitudes, interests, and behaviors of more than 5,500 individuals,” the study concludes, “which reveals that internal consistency is extremely rare. Our study demonstrates that, although there are sex/gender differences in the brain, human brains do not belong to one of two distinct categories: male brain/female brain.”
Looking at scans during the first test of 169 men and 112 women, the research defined “malelike” and “femalelike” as the “33 percent most extreme gender-difference scores on gray matter from 10 regions.” Researchers found little evidence of any male/female consistency across the sample size and only 6% of the brains were consistent with male/female “traits.”
A second analysis of “600 brains from 18- to 26-year-olds found that only 2.4 percent were internally consistent as male or female, while substantial variability was the rule for more than half (52 percent).” The study basically shows what the gender non-conforming and transgender community have been saying for decades, that there are very few individual brains that identify as binary male and female, but are comprised of a vast array of characteristics combining male, female and non-binary connectivity.
The report also stated, “Our results demonstrate that even when analyses are restricted to a small number of brain regions (or connections) showing the largest sex/gender differences, internal consistency is rare and is much less common than substantial variability (i.e., being at the one end of the ‘maleness-femaleness’ continuum on some elements and at the other end on other elements).”
Tel Aviv University psychobiologist Daphna Joel, who was part of the study, wrote that the findings have been consistent with other research on brain development and the hormonal control that is perceived to dominate over the brain’s functions. It was historically thought that the testosterone masculinization of the brain that occurred past the 12th week of gestation was the dominant factor is deciding the male/female difference, but according to the 2011 review in Nature Neouroscience, the development of the brain is far more complex than hormonal influence.
“The idea of a unified ‘masculine’ or ‘feminine’ personality turns out not to describe real people, Jordan-Young told Live Science “she said. “It describes stereotypes to which we constantly compare ourselves and each other, but more people are ‘gender non-conforming’ than we generally realize.”