dvcochran
Grandmaster
The key word in you post is some. Some people, not most. We can all be put into some categories (black, white, Asian, etc...) but that is way too specific of an example to pool everyone under.Yes that is a given. Robert Sapolski has some good lectures on line that explains how the wide range of nature vs nuture influences effect us and brings our behavior right down to the individual level. But he is a firm believer in the idea we have no free will.
The brain circuitry doesn't change. All that changed was how we perceived the individual. There are studies that were done where someone was given a sports team hat to wear and what was shown is that if the test subject was from a different city from the sports team they were more likely to put that person in a "them" catagory, but then the person said he was born in the same city as the test subject and wow all of the sudden that person becomes recognized as an "US".