Male Brains and Female Brains Look Pretty Much the Same, According to Science

There's an entire sect of the self-help industry devoted to decoding the opposite sex's brain: Think like a man to get ahead, think like a woman to get in her pants, blah blah blah. For a long time, we've believed that men and women's brains were just plain different—and there is some science to suggest that's true. Previous research has suggested that male brains tend to be larger in volume, or that female brains are just wired differently, with better interconnectivity between the left and right hemispheres in women's brains. But according to a study published today in the Proceedings of the National Academy of Sciences, that's all bullshit, because it's actually really hard to tell the difference between a "male brain" and a "female brain" by looking at one.

Researchers compared MRI scans of more than 1,400 brains, focusing on structural differences between male and female brains—things like the volume of gray matter, the size of the hippocampus (which is responsible for memory and emotions,) or connections to specific parts of the brain. Some traits were more common in women, others were more common in men (consistent with some of the previous research), but only 6 percent of brains had "all male" or "all female" traits. The majority were a combination of both.

The research comes on the heels of another study, published earlier this month, which dispelled the notion that the hippocampus is larger in women. According to that study, which analyzed structural MRIs, there was no difference in size.

This is all to say that the human brain can't be neatly categorized into one of two categories, but that instead, as the researchers of today's study put it, "each brain is a unique mosaic of features."

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