There are some differences between men and women — like the amount of testosterone and estrogen they produce — that are undeniably there. Others are more imagined, and fall into generalizations and stereotypes. For those attempting to explain perceived differences between the sexes, the brain is the first place they’d think to look. If there was a solid, physical difference between male and female brains, that could surely explain any behavioral differences, right?

When it comes to the hippocampus, a crucial part of the brain previously thought to be larger in females, there really isn’t any difference at all between men and women. Research from the Rosalind Franklin University of Medicine and Science showed no significant difference in hippocampal size between the sexes. Dr. Lise Elliot, associate professor of neuroscience at the university’s medical school, headed a team in a meta-analysis of the structural MRI volumes, meaning that they combined the findings from many independent studies into one review. The researchers looked at findings from 76 papers.

“Sex differences in the brain are irresistible to those looking to explain stereotypic differences between men and women,” said Eliot in a press release. “They often make a big splash, in spite of being based on small samples. But as we explore multiple datasets and are able to coalesce very large samples of males and females, we find these differences often disappear or are trivial.”

There are two hippocampi in the human brain, one on both sides of the brain beneath the cerebral cortex. The structure is commonly associated with memory, spatial navigation, and inhibition. Previously, a common theory claimed that a disproportionately large hippocampus explains females’ tendency toward stronger interpersonal skills, emotional expressiveness, and better verbal memory.

“Many people believe there is such a thing as a ‘male brain’ and a ‘female brain,’” Eliot said. “But when you look beyond the popularized studies — at collections of all the data — you often find that the differences are minimal.

Other meta-analyses have also disproved similar purported sex differences in the brain, according to Eliot. There is no difference in the size of the white matter that allows the two sides of the brain to communicate (the corpus callosum), nor do men and women differ in the way their two brain hemispheres process language.

Source: Tan A, Ma W, Vira A, Marwha D, Eliot L. The human hippocampus is not sexually-dimorphic: Meta-analysis of structural MRI volumes. Neuroimage. 2015.