TODAY, we are just in the early stages of understanding the complexity of the brain. Small structural differences in the brains of men and women may mean nothing or they may have significance. For the most part, we just don't know. What's important is that women don't cede to men the ability to reason, organize and lead, thanks to our "different" brains. If we do, we'll be marching backward into history.That's why I'm alarmed to see Dr. Louann Brizendine, a California psychiatrist, come back with more dollops of myth and pseudoscience in her new book The Male Brain (Broadway; 2010). The media swooned over her first book, The Female Brain (Broadway), published in 2006, which, like this sequel, is all about how the brains of men and women are so vastly different.

The Female Brain got massive coverage, including interviews on most of the TV morning network shows, 20-20 and CNN. It was also featured in The New York Times Magazine, the Washington Post, the Chicago Tribune and Oprah magazine, among others.

Scientific critics were not so kind. The British journal Nature called it "riddled with scientific errors." Others pointed out that Brizendine jumped to conclusions based on tiny samples or very early research, used animal data to discuss human behavior and was sometimes just plain misinformed. She had to remove from the book a claim that women use 20,000 words a day while men use only 7,000. There was harder evidence behind the idea that men and women talk the same amount.

The new book is breezy and readable, but has many of the same problems. Critic Emily Bazelon points out in her excellent New York Times review that "You'd never know from reading Brizendine that beneath the sea she blithely sails are depths that researchers have only just begun to chart."

Men, Brizendine claims, are rational systemizers and problem solvers who don't comprehend emotion. Women wail desperately at their mates, "You don't understand!" while the men look blank. Her major citation, Bazelon points out, is a single, very small 2008 brain-scan study of 14 women and 12 men, which found a gender difference in part of a lab experiment that tried to simulate empathy. A great deal of evidence contradicts this tiny study.

Show Some Emotion

Do men lack empathy and fail to understand emotion? Psychologist Faye Crosby of UC–Santa Cruz says no. Crosby methodically examined the major, well-designed, scientific studies comparing males and females with regard to empathy, altruism, cooperativeness, nurturance and intimacy. She found "no conclusive evidence to show that men and women differ from one another in the extent to which they attend to and are good at interpersonal relationships." In fact, in a number of the laboratory studies, men responded more strongly internally to emotional stimuli than women, but women show more emotion outwardly.

Vanderbilt University psychologist Ann Kring, who studied findings on sex differences in emotion, said in a 1998 issue of The Journal of Personality and Social Psychology that: "It is incorrect to make a blanket statement that women are more emotional than men. It is correct to say that women show their emotions more than men."The Male Brain unfortunately tosses another log onto the media blaze about men and women having their "natural" places. Men are the thinkers, the systemizers, the rationalists. Women are the carers and the feelers.

Cambridge University psychologist Simon Baron-Cohen—who wrote the book The Essential Difference (2004)—says that males are good at leadership, decision-making and achievement, while females are suited for "making friends, mothering, gossiping and 'reading' your partner." (He has been quoted in The New York Times, in a Newsweek cover story, in a PBS documentary and in many other major media outlets.) Baron-Cohen bases his claims on one study, conducted in his lab in 2000, of day-old infants purporting to show that baby boys looked longer at mobiles, while day-old baby girls looked longer at human faces.

Elizabeth Spelke, co-director of Harvard's Mind, Brain and Behavior Interfaculty Initiative, utterly demolished this study. It has never been replicated, nor has it appeared in a peer-reviewed journal, she reported. Spelke found the study lacked critical controls against experimenter bias and was not well-designed. Female and male infants were propped up in a parent's lap and shown, side-by-side, an active person or an inanimate object. Since newborns can't hold their heads up independently, their visual preferences could well have been determined by the way their parents held them.

Moreover, a long line of literature flat-out contradicts Baron-Cohen's study, providing evidence that male and female infants tend to respond similarly to people and objects. (Brizendine cites the Baron-Cohen study with nary a nod to the critics.)

Corpus of Evidence

Even books that try to boost women can fall into this trap. In The Natural Leadership Talents of Women (2005), Helen E. Fisher claims women have superior relationship abilities because of the larger size of their corpus callosums, the nerve cables connecting the halves of the brain. "So it's not surprising that women already hold over 60 percent of jobs in the booming service sector of the world economy—another way they lead," she says in the book.But peer-reviewed research finds no difference between men and women in the size of the corpus callosum. If women hold so many jobs in the service sector it's not because of their brains. Maybe it's because those jobs tend be lower-level ones that do not lead to the CEO track, where the power is. Steering women toward "caring, relational jobs" keeps them out of the highest-level positions.We have to tread lightly in the area of brain research, because of its dismal history. In the Victorian era, scientists packed cadaver skulls of white and black females and white and black males with lead pellets to measure brain size. The larger size of the white male brains, it was argued, meant that white males were the natural lords of creation, while the brains of white and black women and black men were "childlike" in comparison. (Researchers used the brains of Hottentots, a group of blacks very small in stature, to rig the results.)

We now know, of course, that slightly larger brains do not make men more intelligent than women. But this "science" helped keep women out of universities and out of the voting booths for years.

Caryl Rivers and Rosalind C. Barnett are authors of 'Same Difference: How Gender Myths Are Hurting Our Relationships, Our Children and Our Jobs.'/

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