People who have lots of friends have certain parts of the brain that are bigger and better connected than those of less sociable types, research has found.
About six brain regions are larger in sociable people and the more friends someone has, the larger these regions are, scans showed.
One of the regions that was larger was the anterior cingulate cortex, which we use to keep track of what others are doing.
Connections between this area and another that is used to work out how others are feeling were especially strong in sociable people.
It’s one of the great questions about the human brain: how and why did it get so damn big?
Various possible explanations exist: to process language perhaps. There’s also all sorts of implications of it being so big: one theory is that we eat meat in order to feed the brain. One obvious effect is that it makes giving birth difficult, getting that head through the pelvis. And that in turn leads to the very long development time of babies.
One of the theories is that there became a self-reinforcing cycle. Larger brains led to more sociability which in turn led to those with ever larger brains having more surviving children. Thus, by this theory, there’s a very strong link between sociability and the size of the brain.
Therefore, by this theory of course, these findings are interesting but not surprising: they’re what we would expect to find.