In particular, scientists in the UK observed that conservatives tended to have a larger amygdala, the part of the brain responsible for emotion and anxiety, and a smaller anterior cingulate, which supplies bravery and optimism. From the Telegraph:
Prof Geraint Rees, who led the research, said: “We were very surprised to find that there was an area of the brain that we could predict political attitude.
"It is very surprising because it does suggest there is something about political attitude that is encoded in our brain structure through our experience or that there is something in our brain structure that determines or results in political attitude.”
Prof Rees and his team, who carried out the research for the Today programme on BBC Radio 4, looked at the brain make up of the Labour MP Stephen Pound and Alan Duncan, the Conservative Minister of State for International Development using a scanner.
They also questioned a further 90 students, who had already been scanned for other studies, about their political views.
The results, which will be published next year, back up a study that showed that some people were born with a “Liberal Gene” that makes people more likely to seek out less conventional political views.