This brain area, located behind the eyes, grows rapidly during childhood as we start to grasp social cues. But it is unclear why or when it stops growing in some people.
Damage to it is linked to behaving inappropriately in social situations or, in extreme cases, with personality disorders.
Professor Chris Frith of UCL said adapting to others is very important.
"It makes people like you more, and it be very useful if other people have more information than you have as it shows you what they value most," he said.
"My guess is that it's better if more people are conformists than rebels, but you need a few rebels otherwise there would be no progress."
Conformity was studied in the Ash Experiment in the US in 1951. In tests people were found to give an answer they knew was wrong simply because they had heard other participants say it.
- DAILY MAIL