Despite a decades-long attempt to ignore the male/female dichotomy, new research strongly indicates that the determinants of intelligence in the brains of men are overwhelmingly different from those in the brains of women.
Recent research conducted by Srikanth Ryali, et al, at Stanford University used artificial intelligence (AI) methodology to study the brain activity of about 1,500 young people aged 20-35 years.
“Sex is an important biological factor that influences human behavior, impacting brain function and the manifestation of psychiatric and neurological disorders,” the researchers began in the body of their paper. It was published in February at the Proceedings of the National Academy of Sciences (PNAS).
They noted, nevertheless, that “our understanding of sex differences in human functional brain organization and their behavioral consequences has been hindered by inconsistent findings and a lack of replication.”
Vinod Menon, Ph.D., professor of psychiatry and behavioral sciences and director of the Stanford Cognitive and Systems Neuroscience Laboratory – and the study’s senior author – emphasized in comments to the Stanford Medicine News Center that the research was especially motivated by the knowledge that “sex plays a crucial role in human brain development, in aging, and in the manifestation of psychiatric and neurological disorders.”
After using AI technology to create a neural network model, which learns to classify brain imaging data, researchers found the model was ultimately able to tell if a brain scan came from a man or a woman in most cases.
“These models worked really well because we successfully separated brain patterns between sexes,” Menon told Stanford Medicine. “That tells me that overlooking sex differences in brain organization could lead us to miss key factors underlying neuropsychiatric disorders.”
The researchers concluded:
Our results demonstrate that sex differences in functional brain dynamics are not only highly replicable and generalizable but also behaviorally relevant, challenging the notion of a continuum in male-female brain organization. Our findings underscore the crucial role of sex as a biological determinant in human brain organization, have significant implications for developing personalized sex-specific biomarkers in psychiatric and neurological disorders, and provide innovative AI-based computational tools for future research.
Family physician and psychologist Leonard Sax, M.D., Ph.D., highlighted the research last week at the Institute for Family Studies (IFS) as he chronicled his own experience over the years in dealing with ideological attempts to eliminate the male-female dichotomy, first to establish women’s equal rights to education and opportunity, but, more recently, to undermine the entire concept of male-female sex in order to create a genderless society.
“In my visits to more than 500 schools over the past 23 years,” Sax reported, those schools
actively “problematize” and “deconstruct” the male/female dichotomy. Some school districts now even discourage the use of the words “boys” and “girls” on the grounds that those words reinforce the heteronormative binary. And the phrase “ladies and gentlemen” is even more offensive to some.
Sympathetic to the problems associated with “Western sexism,” nevertheless, Sax explained the bottom line:
I want my daughter to have the same opportunities as any boy. The problem is that there are hardwired female/male differences, and those differences matter. Ignoring reality is never best practice.
Sax highlighted the crux of the AI research:
They found particular patterns of connectivity within male brains that accurately predicted cognitive functions such as intelligence. However, that male model had no predictive power for cognitive functions in women. Conversely, they found patterns of connectivity within female brains that predicted cognitive functions such as intelligence among women. However, that female model had no predictive power for cognitive functions in men. These findings strongly suggest that the determinants of intelligence in male brains are profoundly different from the determinants of intelligence in female brains.
The physician and psychologist explained how he uses research about differences in the brains of males and females in his work with families with children of both sexes who express concern that a male child is behaving differently than his older female sibling.
“Don’t compare your son to your daughter,” he advises. “If you must compare your son to anybody, compare your son to other boys.”
“Parents need to know that girls mature faster than boys,” he observed. “A study of 829 MRI scans from individuals 3 to 27 years of age showed that girls reach the half-way point in brain development just before 11 years of age; boys, not until almost 15 years.”
The “challenge,” he asserted,
is to understand and indeed celebrate female/male differences while insisting on equal rights and equal opportunities for all girls and boys. This means, the opportunity for a boy to grow up to be a full-time stay-at-home father if that’s what he wants to be, and the opportunity for a girl to grow up to be an Army Ranger or a physicist if that’s what she wants.
“Let’s not ignore gender differences or pretend that they don’t exist,” Sax urged. “Let’s use our understanding of the emerging science of sex differences to boost motivation and outcomes for both boys and girls.”
