Louann Brizendine is a neuropsychiatrist who seems intent on bolstering sex stereotypes with poor science. Presumably in the service of promoting a new book, she has an article on CNN which attempts to explain ‘why men obsess over sex’ but which has lots of odd errors and strange unsubstantiated claims.
The thing that immediately struck me was in the initial paragraphs:
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.
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.
Male and female humans are indeed the same species, but we are not a species which has a dorsal premammillary nucleus because it’s only been identified in the rat.
Furthermore, there is no reliable evidence that amygdala size differs between the sexes in humans and a recent study that looked specifically at this issue found no difference.
The rest of the article is full of Brizendine’s usual style which is to take a common stereotype of male or female behaviour and then to ‘explain’ it with a overly-simple, one dimensional and usually not directly tested brain explanation.
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.
Got that? Testosterone is responsible for men looking at breasts, perhaps even falling into an irresistible tit-driven trance, and we can’t help it. Are there any scientific studies on whether hooter staring is related to testosterone levels? (Sadly) No.
And there’s plenty more unlikely claims along similar lines. Apparently oxytocin is responsible for ‘nice’ grandpas whereas ‘grumpy’ grandpas can be explained by a drop in testosterone in later life.
Please make it stop.
UPDATE: Thanks to @willoller and Bergen who pointed out that the dorsal premammilliary nuclei have been identified in humans. Interestingly, however, I can only find one study which has ever investigated it in humans and nothing which suggests it is a “defend your turf” area. This conclusion seems entirely drawn from rat studies (e.g. this one) and what Brizendine seems to be doing, in this and other recent articles, is taking findings from rat studies and talking as if they were directly relevant to humans which is dubious to say the least.