But the relationship was not as strong. But the point is, in women, whether it was verbal or non-verbal intelligence, brain size was positively correlated — that means the bigger the brain, the better they did.

This is essentially the first study that is actually looking at the size of the brain directly and not through imaging.

What we're suggesting, and this remains to be tested by further work, that in men it isn't the size of the overall brain that is correlated with how well they do on all these mazes and three-dimensional perception tests, but it might be the structure, it might be the size or the anatomical microscopic structure of the region in the brain that is important for that kind of thinking.

What is very clear is that there is a correlation between brain size and intelligence, particularly verbal ability.