My wife asked me to blog about this article on CNN because, she said, “it’s really terrible, and it shouldn’t be on CNN”. I usually do what my wife tells me to do, so I’m blogging about it. It’s by Louann Brizendine, M.D., author of the absolutely awful controversial book The Female Brain, and now, its manly counterpart, The Male Brain. From what I can gather, the CNN article, which is titled Love, Sex, and the Male Brain, is a precis of Brizendine’s new book (though I have no intention of reading the book to make sure). The article is pretty short, so I’ll go through the first half of it paragraph-by-paragraph. But I’ll warn you right now that it isn’t pretty, and will likely anger anyone with even a modicum of training in psychology or neuroscience.
Although women the world over have been doing it for centuries, we can’t really blame a guy for being a guy. And this is especially true now that we know that the male and female brains have some profound differences.
Our brains are mostly alike. We are the same species, after all. But the differences can sometimes make it seem like we are worlds apart.
So far, nothing terribly wrong here, just standard pop psychology platitudes. But it goes quickly downhill.
The “defend your turf” area — dorsal premammillary nucleus — is larger in the male brain and contains special circuits to detect territorial challenges by other males. And his amygdala, the alarm system for threats, fear and danger is also larger in men. These brain differences make men more alert than women to potential turf threats.
As Vaughan notes over at Mind Hacks, the dorsal premammillary nucleus (PMD) hasn’t been identified in humans, so it’s unclear exactly what chunk of tissue Brizendine’s referring to–let alone where the evidence that there are gender differences in humans might come from. The claim that the PMD is a “defend your turf” area might be plausible, if oh, I don’t know, you happen to think that the way rats behave under narrowly circumscribed laboratory conditions when confronted by an aggressor is a good guide to normal interactions between human males. (Then again, given that PMD lesions impair rats from running away when exposed to a cat, Brizendine could just as easily have concluded that the dorsal premammillary nucleus is the “fleeing” part of the brain.)
The amygdala claim is marginally less ridiculous: it’s not entirely clear that the amygdala is “the alarm system for threats, fear and danger”, but at least that’s a claim you can make with a straight face, since it’s one fairly common view among neuroscientists. What’s not really defensible is the claim that larger amygdalae “make men more alert than women to potential turf threats”, because (a) there’s limited evidence that the male amygdala really is larger than the female amygdala and (b) if such a difference exists, it’s very small, and (c) it’s not clear in any case how you go from a small between-group difference to the notion that somehow the amygdala is the reason why men maintain little interpersonal fiefdoms and women don’t.
Meanwhile, the “I feel what you feel” part of the brain — mirror-neuron system — is larger and more active in the female brain. So women can naturally get in sync with others’ emotions by reading facial expressions, interpreting tone of voice and other nonverbal emotional cues.
This falls under the rubric of “not even wrong“. The mirror neuron system isn’t a single “part of the brain”; current evidence suggests that neurons that show mirroring properties are widely distributed throughout multiple frontoparietal regions. So I don’t really know what brain region Brizendine is referring to (the fact that she never cites any empirical studies in support of her claims is something of an inconvenience in that respect). And even if I did know, it’s a safe bet it wouldn’t be the “I feel what you feel” brain region, because, as far as I know, no such thing exists. The central claim regarding mirror neurons isn’t that they support empathy per se, but that they support a much more basic type of representation–namely, abstract conceptual (as opposed to sensory/motor) representation of actions. And even that much weaker notion is controversial; for example, Greg Hickok has a couple of recent posts (and a widely circulated paper) arguing against it. No one, as far as I know, has provided any kind of serious evidence linking the mirror neuron system to females’ (modestly) superior nonverbal decoding ability.
Perhaps the biggest difference between the male and female brain is that men have a sexual pursuit area that is 2.5 times larger than the one in the female brain. Not only that, but beginning in their teens, they produce 200 to 250 percent more testosterone than they did during pre-adolescence.
Maybe the silliest paragraph in the whole article. Not only do I not know what region Brizendine is talking about here, I have absolutely no clue what the “sexual pursuit area” might be. It could be just me, I suppose, but I just searched Google Scholar for “sexual pursuit area” and got… zero hits. Is it a visual region? A part of the hypothalamus? The notoriously grabby motor cortex hand area? No one knows, and Brizendine isn’t telling. Off-hand, I don’t know of any region of the human brain that shows the degree of sexual dimorphism Brizendine claims here.
If testosterone were beer, a 9-year-old boy would be getting the equivalent of a cup a day. But a 15-year-old would be getting the equivalent of nearly two gallons a day. This fuels their sexual engines and makes it impossible for them to stop thinking about female body parts and sex.
If each fiber of chest hair was a tree, a 12-year-old boy would have a Bonsai sitting on the kitchen counter, and a 30-year-old man would own Roosevelt National Forest. What you’re supposed to learn from this analogy, I honestly couldn’t tell you. It’s hard for me to think clearly about trees and hair you see, seeing as how I find it impossible to stop thinking about female body parts while I’m trying to write this.
All that testosterone drives the “Man Trance”– that glazed-eye look a man gets when he sees breasts. As a woman who was among the ranks of the early feminists, I wish I could say that men can stop themselves from entering this trance. But the truth is, they can’t. Their visual brain circuits are always on the lookout for fertile mates. Whether or not they intend to pursue a visual enticement, they have to check out the goods.
To a man, this is the most natural response in the world, so he’s dismayed by how betrayed his wife or girlfriend feels when she sees him eyeing another woman. Men look at attractive women the way we look at pretty butterflies. They catch the male brain’s attention for a second, but then they flit out of his mind. Five minutes later, while we’re still fuming, he’s deciding whether he wants ribs or chicken for dinner. He asks us, “What’s wrong?” We say, “Nothing.” He shrugs and turns on the TV. We smolder and fear that he’ll leave us for another woman.
This actually isn’t so bad if you ignore the condescending “men are animals with no self-control” implication and pretend Brizendine had just made the indisputably true but utterly banal observation that men, on average, like to ogle women more than women, on average, like to ogle men.
Not surprisingly, the different objectives that men and women have in mating games put us on opposing teams — at least at first. The female brain is driven to seek security and reliability in a potential mate before she has sex. But a male brain is fueled to mate and mate again. Until, that is, he mates for life.
So men are driven to sleep around, again and again… until they stop sleeping around. It’s tautological and profound at the same time!
Despite stereotypes to the contrary, the male brain can fall in love just as hard and fast as the female brain, and maybe more so. When he meets and sets his sights on capturing “the one,” mating with her becomes his prime directive. And when he succeeds, his brain makes an indelible imprint of her. Lust and love collide and he’s hooked.
Failure to operationalize complex construct of “love” in a measurable way… check. Total lack of evidence in support of claim that men and women are equally love-crazy… check. Oblique reference to Star Trek universe… check. What’s not to like?
A man in hot pursuit of a mate doesn’t even remotely resemble a devoted, doting daddy. But that’s what his future holds. When his mate becomes pregnant, she’ll emit pheromones that will waft into his nostrils, stimulating his brain to make more of a hormone called prolactin. Her pheromones will also cause his testosterone production to drop by 30 percent.
You know, on the off-chance that something like this is actually true, I think it’s actually kind of neat. But I just can’t bring myself to do a literature search, because I’m pretty sure I’ll discover that the jury is still out on whether humans even emit and detect pheromones (ok, I know this isn’t a completely baseless claim), or that there’s little to no evidence of a causal relationship between women releasing pheromones and testosterone levels dropping in men. I don’t like to be disappointed, you see; it turns out it’s much easier to just decide what you want to believe ahead of time and then contort available evidence to fit that view.
Anyway, we’re only half-way through the article; Brizendine goes on in similar fashion for several hundred more words. Highlights include the origin of male poker face, the conflation of correlation and causation in sociable elderly men, and the effects of oxytocin on your grandfather. You should go read the reset of it if you practice masochism; I’m too full of rage depressed to write about it any more.
Setting aside the blatant exercise in irresponsible scientific communication (Brizendine has an MD, and appears to be at least nominally affiliated with UCSF’s psychiatry department, so ignorance shouldn’t really be a valid excuse here), I guess what I’d really like to know is what goes through Brizendine’s mind when she writes this sort of dreck. Does she really believe the ludicrous claims she makes? Is she fully aware she’s grossly distorting the empirical evidence if not outright confabulating, and is simply in it for the money? Or does she rationalize it as a case of the ends justifying the means, thinking the message she’s presenting is basically right, so it’s ok if nearly all a few of the details go missing in the process?
I understand that presenting scientific evidence in an accurate and entertaining manner is a difficult business, and many people who work hard at it still get it wrong pretty often (I make mistakes in my posts here all the time!). But many scientists still manage to find time in their busy schedules to write popular science books that present the science in an accessible way without having to make up ridiculous stories just to keep the reader entertained (Steven Pinker, Antonio Damasio, and Dan Gilbert are just a few of the first ones that spring to mind). And then there are amazing science writers like Carl Zimmer and David Dobbs who don’t necessarily have any professional training in the areas they write about, but still put in the time and energy to make sure they get the details right, and consistently write stories that blow me away (the highest compliment I can pay to a science story is that it makes me think “I wish I studied that“, and Zimmer’s articles routinely do that). That type of intellectual honesty is essential, because there’s really no point in going to the trouble of doing most scientific research if people get to disregard any findings they disagree with on ideological or aesthetic grounds, or can make up any evidence they like to fit their claims.
The sad thing is that Brizendine’s new book will probably sell more copies in its first year out than Carl Zimmer’s entire back catalogue. And it’s not going to sell all those copies because it’s a careful meditation on the subtle differences between genders that scientists have uncovered; it’s going to fly off the shelves because it basically regurgitates popular stereotypes about gender differences with a seemingly authoritative scientific backing. Instead of evaluating and challenging many of those notions with actual empirical data, people who read Brizendine’s work will now get to say “science proves it!”, making it that much more difficult for responsible scientists and journalists to tell the public what’s really true about gender differences.
You might say (or at least, Brizendine might say) that this is all well and good, but hopelessly naive and idealistic, and that telling an accurate story is always going to be less important than telling the public what it wants to hear about science, because the latter is the only way to ensure continued funding for and interest in scientific research. This isn’t that uncommon a sentiment; I’ve even heard a number of scientists who I otherwise have a great deal of respect for say something like this. But I think Brizendine’s work underscores the typical outcome of that type of reasoning: once you allow yourself to relax the standards for what counts as evidence, it becomes quite easy to rationalize almost any rhetorical abuse of science, and ultimately you abuse the public’s trust while muddying the waters for working scientists.
As with so many other things, I think Richard Feynman summed up this sentiment best:
I would like to add something that’s not essential to the science, but something I kind of believe, which is that you should not fool the layman when you’re talking as a scientist. I am not trying to tell you what to do about cheating on your wife, or fooling your girlfriend, or something like that, when you’re not trying to be a scientist, but just trying to be an ordinary human being. We’ll leave those problems up to you and your rabbi. I’m talking about a specific, extra type of integrity that is not lying, but bending over backwards to show how you are maybe wrong, that you ought to have when acting as a scientist. And this is our responsibility as scientists, certainly to other scientists, and I think to laymen.
For example, I was a little surprised when I was talking to a friend who was going to go on the radio. He does work on cosmology and astronomy, and he wondered how he would explain what the applications of this work were. “Well,” I said, “there aren’t any.” He said, “Yes, but then we won’t get support for more research of this kind.” I think that’s kind of dishonest. If you’re representing yourself as a scientist, then you should explain to the layman what you’re doing–and if they don’t want to support you under those circumstances, then that’s their decision.
No one doubts that men and women differ from one another, and the study of gender differences is an active and important area of psychology and neuroscience. But I can’t for the life of me see any merit in telling the public that men can’t stop thinking about breasts because they’re full of the beer-equivalent of two gallons of testosterone.
[Update 3/25: plenty of other scathing critiques pop up in the blogosphere today: Language Log, Salon, and Neuronarrative, and no doubt many others…]