The Essential Difference: The Truth about the Male and Female Brain

Of math and makeup tips

"The female brain is predominantly hard-wired for empathy. The male brain is predominantly hard-wired for understanding and building systems."

That thesis, the cornerstone of Simon Baron-Cohen's new book, The Essential Difference: The Truth About the Male and Female Brain, appears to reinforce the worst kind of gender stereotypes: Girls are good listeners who bolster their friends' egos with flattery and happy makeup tips (yes, that's an actual example of typical female-brain behavior from Baron-Cohen's book) but are hopeless at math. Boys gravitate toward tractors, fire engines and VCR buttons as tikes and grow up to be good at computers and stuff, but are no good at the niceties of social situations. And in both cases, the author maintains, biology, not society is primarily responsible.

To be fair, Baron-Cohen, a Cambridge University professor of psychology and psychiatry specializing in sex differences and autism, is painfully aware that his theory might alarm some of his readers, causing them to reject it out of hand or to "go halfway down the track" with him only to avert their eyes from "things that they would prefer not to see." Nevertheless, he insists that the information in his book "can be used progressively." "Society needs both of the main brain types," he writes in the book's closing pages.

But I'm showing my poor systemizing skills here and getting ahead of myself.

Baron-Cohen's research shows that the citizens of the world can be divided into two groups: those who possess a female or "type E" (for empathizing) brain and those who possess a male or "type S" (for systemizing) brain. People with "type E" brains are "individuals in whom empathizing is stronger (more developed) than systemizing." They are better at identifying someone else's emotions and thoughts and responding to them than, say, finding the best route home on a map.

"Type S"-brained people have the opposite skills. They may excel at analyzing, exploring and constructing systems — "the systemizer intuitively figures out how things work or extracts the underlying rules that govern the behavior of a system ... a pond, a vehicle, a plant, a library catalog, a musical composition, a cricket bowl, or even an army unit." But confront them with someone in tears for reasons that are not readily apparent to them and they're downright flummoxed.

You do not have to be female to be "type E" (though Baron-Cohen would say that you "type E" men possess a female brain) nor male to be "type S," but Baron-Cohen says most women do tend to be the former and men the latter. There is also a third type of brain, "type B" or balanced, in which your systemizing and empathizing skills are both equally strong, though this sort of brain would appear to be rather rare.

Readers can find out which brain they have by taking three of four fairly entertaining tests appended to the back of the book. (In combination, they're sort of like that old Myers-Briggs test you took in college that had everyone milling around saying "Hi, I'm an EFPQ" or whatever the heck it was. Remember that thing?)

The first test is called "The 'Reading the Mind in the Eyes' Test," and as its name implies, measures your ability to gauge a person's state of mind by looking at photos of only their eyes. Is this droopy-eyed person "terrified," "upset," "arrogant" or "annoyed"? Take a guess and skip to the answers to see how you fare. (Me, I got 27 right out of 36, which puts me smack-dab in the middle of the "typical" range.)

Two other tests assess your empathy quotient (EQ) and systemizing quotient (SQ) by asking you how strongly you agree with each of a series of statements. If you "strongly agree" with the assertion that "I can easily tell if someone else wants to enter a conversation," for instance, you get two points on the EQ. "Definitely agree"-ing with the statement "I prefer to read non-fiction than fiction," meanwhile, will get you two points on your SQ. (I apparently have an above-average EQ and a lowish-average SQ, even for a woman.)

Be forewarned, as pop-psych-ish as this all sounds, Baron-Cohen does not see his book as suitable for the "Mars-Venus" set. Far from it. In fact, Baron-Cohen apparently believes that his tome is, to some degree, the anti-"Mars-Venus."

"Although it may make amusing reading," he writes. "it is not helpful scientifically to imagine that 'men are from Mars and women are from Venus' ... The joke about our coming from two different planets distracts us from the serious fact that both sexes have evolved on the same planet and yet tend to display differences in the way we think ... Moreover, the view that men are from Mars and women Venus paints the differences between the two sexes as too extreme. The two sexes are different, but are not so different that we cannot understand each other." Surely, Baron-Cohen is not to blame for the "Mars-Venus"-esque jacket copy beginning, "We all know the opposite sex can be a baffling, even infuriating, species."

After all, he is a scientist. Nevertheless, not until Chapter 8 does he finally arrive at the biological explanation upon which his thesis rests. To get there, readers have to slog through seven chapters of endnoted but clichéd assertions like, say, (and I'm flipping through and picking a sentence at random here) "Girls in later childhood spend a lot of time talking about who is whose best friend, and get very emotional if they are excluded from relationships on the playground. Sulking is not uncommon." Or "Boys tend to play group games (such as soccer and baseball) much more than girls do. This is partly a sign of the importance of group membership to boys, and partly a reflection of their interest in rule-based activities."

I mean, really, pages and pages of this stuff, some of it seemingly well researched. Some pulled from who knows where. For instance, to support his assertion that boys have a superior mathematical ability across cultures, after allowing that their work in school might be "less neat" than girls', Baron-Cohen looks at the entrants in the International Mathematical Olympiad, "in which the world's best mathematicians compete against each other."

"You can look up the winners on the Web if you are interested," he writes. "You will notice immediately that they are nearly all male. The Olympiad winners are listed by name, not by sex, but one can have a good guess at the sex of someone called Sanjay, David, Sergei, or Adam."

This is valuable scientific evidence?

When Baron-Cohen does get to the biological evidence, he starts out weak, citing a study that finds that male monkeys "play-fight" more than females of the species, which he says could be "a sign of males' reduced social sensitivity to others" as well as an early awareness of a social order, or system. Female monkeys, meanwhile, show a stronger interest in babies, which "may be a marker of their increased emotional sensitivity to others, especially vulnerable others."

Slightly more convincing is a study of rats in which the males were found to be better at finding their way through mazes. Baron-Cohen contends that this marginally supports his theory that men are better than women at reading maps. "In both the human and rat studies, a male superiority has been established when geometric (systemic) cues are available. Females tend to rely on landmarks (objects) in the room," which he says is not very systematic or reliable method. (Landmarks sometimes move, and then where are you?)

Delving further into biology, Baron-Cohen finally gets cookin'. First off, hormones appear to play a factor in gender-typical behavior. Higher levels of testosterone, particularly in early development, he maintains, citing studies on everyone from rats to men with "very small testes" to male-to-female and female-to-male transsexuals, lead to an increased aptitude for systems and a decreased aptitude for emotional relationships. What's more, fetal testosterone may also affect the rate of growth of the brain's two hemispheres: the higher the testosterone level, the faster the growth of the right hemisphere, which has been linked to spatial ability, in which systemizing plays a role. The left side of the brain, meanwhile, is linked to language abilities, which is a key component of empathizing, Baron-Cohen says.

One particularly interesting study cited in the book finds that women tend to have larger left feet than right — and larger left ovaries and breasts — as well as dominant left brain hemispheres. These "left-greater" people tend to score better in language tests. Men, on the other hand, are generally found to have dominant right brain hemispheres — and larger feet and testes. "Right-greater" people have been found to do better on spatial tests.

Still, Baron-Cohen seems much more comfortable when he turns to his area of expertise: autism. (He is the director of Cambridge's Autism Research Centre and has written two books on the subject, Autism: The Facts and Mindblindness.) Here, he argues that autism, which afflicts far more men than women and is characterized by "abnormalities in social development and communication" and "unusually strong obsessional interests," and Asperger Syndrome, similar to autism but found in people with higher IQs and less severe communication issues, are both examples of "the extreme male brain." In other words, these are people for whom the systemizing/empathizing split is heavily weighted toward the former. (For the record, I scored very low on Baron-Cohen's appended Autism Spectrum Quotient test, meaning I show few signs of the syndrome.)

And what of its opposite, the extreme female brain? It's apparently a big mystery: No one knows what such a creature would look like. "Hyperempathizing could be a great asset," Baron-Cohen posits, "and poor systemizing may not be too crippling. It is possible that the extreme female brain is not seen in clinics because it is not maladaptive." If you're a "wonderfully caring person who can rapidly make [others] feel fully understood," you can always get someone else to fix your car, he points out.

Baron-Cohen's defense of the extreme female brain seems almost gallant, and as discomfiting as some of his shakily supported theories may be, he seems to have his heart in the right place. Pointing out continually that his assertions are only generalizations and may not apply to all women and men, he also takes great pains to emphasize that neither empathizing nor systemizing is better than the other but rather that each skill has its own intrinsic value.

"I would weep with disappointment if a reader took home from this book the message that 'all men have lower empathy' or 'all women have lower systemizing skills,'" Baron-Cohen writes in summing up his findings. "Such group statistics say nothing about individuals."

You can't help but feel for the guy. But maybe that's the empathizer in me.

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