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by
Angela Saini
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January 10 - January 12, 2021
Since 2000, Baron-Cohen’s department has made a formidable name for itself. At the time his paper was published, he was just two years away from unveiling a controversial and wide-ranging new theory about men and women, which he has named empathizing-systemizing theory. Its basic message is that the “female” brain is hardwired for empathy, while the “male” brain is built for analyzing and building systems, like cars and computers.
Lolololol what a jackass.
Each day, Connellan would turn up to the maternity ward to see if any mothers had given birth. The experiment itself was simple. “We wanted to contrast social versus mechanical,” she says. So every baby was shown a face, which happened to be Connellan’s own, and a mechanical mobile made from a picture of Connellan’s face. They then measured how long every child looked at each one, if they looked at all.
Are you kidding me?
More socially inclined babies, the researchers hypothesized, would prefer to stare at the face, while more mechanically inclined babies might choose to look at the mobile. “It was quite rudimentary as far as the design,” she recalls. “I felt like it was kind of like a science fair project.”
When the results came in, a large proportion of babies showed no preference for the face or the mobile. But around 40 percent of the baby boys preferred to look at the mobile, compared to a quarter who preferred the face. Meanwhile, around 36 percent of the baby girls preferred the face, while only 17 percent preferred the mobile.
“This difference at birth echoes a pattern we have seen right across the human lifespan. For example, on average, women engage in more ‘consistent’ social smiling.”
Facepalm
Professor of biology and gender studies at Brown University Anne Fausto-Sterling, however, is wary of research that claims to see sex differences in such young children. It’s a controversial area of science, especially given how unpredictable babies can be. It’s also too easily swallowed by parents looking to understand their kids better, she adds.
In 1980 two American researchers, psychologist and primate expert Robert Goy and neuroscientist Bruce McEwen, published a survey of animal experiments from preceding decades that explored the effects of testosterone levels around the time of birth. One study revealed that female rats given a single injection of testosterone on the day they were born showed less sexual behavior associated with females and more that associated with males when they became adults.
Scottish neurologist Peter Behan and the US-based neurologists Norman Geschwind and Albert Galaburda said that studies on rats and rabbits showed how, even before a baby was born, higher than normal levels of testosterone slowed development on the left side of the brain, making the right side more dominant.
Oh boy
At the time, there was no medical way of safely measuring testosterone levels in a living fetus. So Geschwind instead relied on studying people who were left-handed (the right half of the brain tends to control muscles on the left side of the body, and vice versa, so someone with a dominant right half would be more likely to be left-handed).
“He was one of the most distinguished of neurologists,” says Chris McManus, a professor of psychology at University College London, who has spent years dissecting the Geschwind-Behan-Galaburda theory. This was part of the problem with his work on testosterone and the brain, he adds. Geschwind’s eminence in his field made it easy for his theory to be published in important journals, even when it turned out that the evidence for it was worryingly thin.
At the time, it became a grand theory of how the brain was organized, drawing big connections between things that weren’t necessarily connected, and between which the connections hadn’t been proven. It was so broad that, even to this day, researchers have difficulty pinning it down.
Since the 1980s, detailed research using new techniques on animals does seem to suggest that sex hormones affect the brains of fetuses as they develop, leading to small differences in certain behaviors later on. It’s a phenomenon that now has enough evidence behind it that neuroscientists and psychologists feel they cannot ignore it, even if this runs counter to their instincts.
Michael is a regular XY male, but he has five-alpha-reductase deficiency, which means he’s missing the enzyme that converts testosterone into a chemical that’s crucial to developing the sex organs before birth. This means that he was genetically male, but his genitalia were ambiguous.
People with conditions like Michael’s are today described as “intersex.” It’s an umbrella under which many extremely rare conditions sit, including androgen insensitivity syndrome, in which a person with male chromosomes appears entirely female because their body doesn’t recognize testosterone, and congenital adrenal hyperplasia, in which women are born looking female but have high levels of male hormones, which can cause ambiguous genitalia.
Starting with the obvious first, “for gender identity, the differences are huge. Most men think of themselves as men and most women don’t,” she states. “The second thing is sexual orientation. Most women are interested in men, and most men aren’t.” The third one is childhood play behavior. Studying girls with congenital adrenal hyperplasia, with higher than normal levels of testosterone, she found, “Rough-and-tumble play is increased in girls exposed to androgens. They like boys’ toys a bit more, girls’ toys a bit less, and they like to play with boys more than the average girl does, but not
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The fact that research is replicated is crucial. A lot of work in the field of psychology, even the most widely reported on in the press, hasn’t been. If a number of independent scientists come to the same conclusions based on different studies across a broad range of people, then it’s far easier to be confident about the results.
This is so important to Hines that, when I meet her, she goes so far as to warn me that she isn’t even sure about the reliability of some of her own research because it hasn’t yet been replicated elsewhere.
I like this scientist!
She and others found in study after study that boys on average really do prefer to play with trucks and cars, while girls on average prefer dolls. “The main toys are vehicles and dolls. Those are the most gendered type of toys,” she says.
“Between twelve and twenty-four months, children were already showing preferences for sex-typed toys. So, the girls were looking longer at the dolls than at the car, and the boys were looking longer at the car than at the doll,” she says. But at twelve months, both boys and girls spent longer looking at the doll than the car.
“Toy preferences, I like to compare to height,” she explains. “We know that men are taller than women but not all men are taller than all women.
This difference in toy choices, however, is a far leap from the theory that the brains of men and women are deeply structurally different because of how much testosterone they’ve been exposed to. It’s also a considerable distance from Baron-Cohen’s claim that there’s such a thing as a typical male brain and a typical female brain—one that prefers mathematics and another that likes coffee mornings.
Tallying all the scientific data she has seen across all ages, Hines believes that the “sex difference in empathizing and systemizing is about half a standard deviation.” This would be equivalent to a gap of about an inch between the average heights of men and women. It’s small.
Duh. How the hell else would we function socially?
In their 1974 book The Psychology of Sex Differences, American researchers Eleanor Maccoby and Carol Nagy Jacklin picked through an enormous mass of studies looking at similarities and differences between boys and girls. They concluded that the psychological gaps between women and men were far smaller than the differences that existed in society among women and among men.
The overlap between the sexes is so huge, she explains, that scientists have struggled to find and replicate results that suggest that there is a real gap between the sexes. “For the time being, the baby science is not convincingly showing any consistent differences.”
Even studying the tiny minority of girls who have been exposed to higher than usual levels of androgens, adds Hines, while it does tell us something about sex differences, doesn’t tell us that these differences are particularly big. “If genetically I am a girl fetus that produces a bit more androgen, maybe I’ll play a bit more with boys than if I had a bit less. Then maybe I’ll have two friends who are boys, instead of one.”
In a table more than three pages long, she lists the statistical gaps that have been found between the sexes on all kinds of measures, from vocabulary and anxiety about mathematics to aggression and self-esteem. In every case, except for throwing distance and vertical jumping, females are less than one standard deviation apart from males. On many measures, they are less than a tenth of a standard deviation apart, which is indistinguishable in everyday life.
Some have argued that there is statistically more variation among men than among women, which means that even though the average man is no more intelligent than the average woman, there are more men of extremely low intelligence and more men of extremely high intelligence. At the far ends of the bell curve where the overlap ends, they say, the difference becomes clear. This may have been the basis for the controversial point made by Harvard president Lawrence Summers in 2005 when he was hunting for explanations for why there are so many more male than female science professors at top
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In 2008, using populationwide surveys of general intelligence among eleven-year-olds in Scotland, a team of researchers based at the University of Edinburgh confirmed that males did show more variability in their test results. These differences aren’t extreme as some in the past have suggested they are, they note, but they are substantial. At the same time, the authors point out that the biggest effect is seen at the bottom end of the scale. Those with the very lowest intelligence scores tend to be male.
“Mainly it’s at the bottom extreme because they have more developmental disorders,” explains Melissa Hines. “At the upper extreme, it’s not that big a difference.”
In their particular set of data, around two boys for every girl achieved the very highest intelligence test scores. At universities, gaps in the numbers of male and female science professors are usually far bigger.
Led by the Princeton University philosophy professor Sarah-Jane Leslie and University of Illinois psychologist Andrei Cimpian, the researchers asked academics from thirty disciplines across the United States if they believed being a top scholar in their field required “a special aptitude that just can’t be taught.” They found that in those disciplines in which people thought you did need to have an innate gift or talent to succeed, there were fewer female PhDs.
The skepticism came to a head in 2007 when New York psychologists Alison Nash and Giordana Grossi dissected the experiment in forensic detail and catalogued a string of problems, big and small. For one thing, the paper’s grand claim that the experiment’s conclusions were “beyond reasonable doubt” seemed an uncomfortable stretch when, in fact, not even half the boys in the study preferred to stare at the mobile and an even smaller percentage of the girls preferred to stare at the face.
But their most damning criticism was that Connellan knew the sex of at least some of the babies she was testing. This could have caused any number of subtle biases.
At the time, her paper was out before she had been awarded her doctorate, and the flood of criticism came to bite when she turned up to defend her work in front of a panel of reviewers. She was told she had failed.
Baron-Cohen get any consequences ?
When I ask Simon Baron-Cohen to give me his own thoughts on the experiment, he tells me by e-mail, “It was designed thoroughly and was scrutinised through peer review and as such it met the bar for good science. No study is above criticism in the sense that one can always think of ways to improve the study, and I hope when a replication is attempted, it will also be improved.” In fact, replication has been one of the biggest problems for the experiment. To date, nobody has attempted to copy it to check if the findings were reliable.
Baron-Cohen, however, tells me that “the fact that the study hasn’t yet been replicated does not invalidate it at all. It simply means we are still awaiting replication.” One explanation he gives for why no other researchers have tried to copy it is that babies are difficult to test, which means you need large groups to get a reliable result. “Second, it appears that testing for psychological sex differences in neonates still attracts a fair amount of controversy. So some researchers may have been deterred by not wanting to walk into a potential political minefield,” he adds.
Jennifer Connellan has since abandoned the minefield altogether. Her career in Simon Baron-Cohen’s lab turned out to be brief. After getting her degree, she left Cambridge to join Pepperdine University. Today, she runs a tutoring company in California.
Baron-Cohen, meanwhile, presses on in trying to establish links between levels of testosterone before birth and sex differences in the brain. In 2002 he and another postgraduate student, Svetlana Lutchmaya, claimed that twelve-month-old girls they observed in experiments made more eye contact than boys of the same age did. This study has been cited by other researchers more than two hundred times.
Melissa Hines tells me that Baron-Cohen’s results didn’t show a direct link between them and high fetal testosterone levels. “That was like the ultimate test, and there was no correlation between testosterone and getting an autism spectrum diagnosis,” she says. “That’s just one study, but it doesn’t support it.”
Without evidence of a clear connection between the “extreme male brain” and testosterone, when their findings were published in the journal Molecular Psychiatry in 2014, Baron-Cohen and his colleagues instead claimed to see a correlation between autism and a mixture of hormones, including testosterone, but also the female sex hormones, progesterone and estrogen.
Ffs
Hines has since run her own study of correlations between fetal testosterone levels and autistic traits on children with congenital adrenal hyperplasia, which was published in the Journal of Child Psychology and Psychiatry in 2016. She found no link.
Fausto-Sterling belongs to a vanguard of biologists and psychologists who see the nature versus nurture question as old-fashioned. “There is a better way of looking at the body and how it works in the world, and understanding the body as a socially formed entity, which it is,” she explains.
“I think that people tend to think of this in an either-or kind of way,” agrees Teodora Gliga. Either girls and boys are born very different or they’re the same. The scientific picture emerging now is that there may be very small biological differences, but that these can be so easily reinforced by society that they appear much bigger as a child grows.
So for example, in physical abilities, if we push boys to be more active and to deal with danger, then of course later in life when they’re children, they will look different. But that does not mean the differences were in the biology,” says Gliga.
Instead of the binary categories we have now, Fausto-Sterling believes that every individual should be thought of as a developmental system—a unique and ever-changing product of upbringing, culture, history, and experience, as well as biology.
One line of research that hasn’t been fully explored, for example, is counting exactly how many toys babies are given in the first year of life, and what kinds of toys they are.
The impact of actions like these, small as they may seem, can be long lasting. “If that kind of interaction is going on iteratively in the early months, then if at some point he does reach out and grab, when he’s big enough to do that, at four months, five months, or six months, he’s going to get a very positive reinforcing response from his mother,” Fausto-Sterling explains.
Fausto-Sterling adds that evidence is emerging from her team’s observations of mothers that boys are also handled differently from girls, which might be influencing the way they grow.
Work like hers, while in its early days, reinforces that countless little thumb marks are in the ball of dough that is a developing child. Hormonal effects on the brain or other deep-seated biological gaps aren’t necessarily the most powerful reason for the gaps we see between the sexes.
In 2013 a team from Taiwan, Cyprus, and the United Kingdom (in which, incidentally, one member was neuroscientist Simon Baron-Cohen) highlighted another. They got together a large number of independent studies into sex differences in brain volume and density to see what they could tell us in summary. In their paper published the following year, the team proclaimed that men’s brains were typically bigger by volume than women’s brains. The gap ranges from 8 to 13 percent.
