Question: Can the shape and size of people's brains differ and if so could this be an explanation about why some are more prominent than others in certain aspects as their brain is shaped towards certain aspects? For example could someone have a better memory because of the shape and size of their hippocampus?

anon answered on 11 Mar 2021:

Hi JoeL,

They can differ in size, yes. This was a quite a popular topic in the 1700s where they thought if you had a lump on your head in one particular area and say were really aggressive that this was the ‘aggressive brain region’ – it’s called phrenology, though it has been completely discredited now!
Recently though, there is a great study about London taxi drivers who do indeed have larger hippocampus! Though I am unsure which come first – the larger hippocampus or the better memory? Interesting stuff!
Another thing I would like to add is there is a bit of theory in non-scientists that those with larger brains in general are more intelligent. Whilst it is true that they have more grey matter volume, the size itself is not a causal factor.
I think brain differences are also functional as well as structural when it comes to differences in cognition (such as memory). If you think of neuroplasticity (those that fire together wire together), where the brains neurons strengthen and weaken in number dependent on how much is used in that task (like memorising London streets). It is definitely a combination of the two.