Pointing to a review at American Scientist, Mind Hacks succinctly summarizes this point from the book “Brain and Culture: Neurobiology, Ideology, and Social Change.”
Fearing the unfamiliar:
The reason that the distrust of people with a different skin color, different values or a different ideology is so prevalent is because the early development of crucial brain pathways makes it hard for people to accept new and unfamiliar experiences.
Bruce Wexler argues that when people are faced with information that does not agree with their internal structures, they deny, discredit, reinterpret or forget that information.
When changes in the environment are great, corresponding internal changes are accompanied by distress and dysfunction. The inability to reconcile differences between strange others and ingrained notions of “humanness” can culminate in violence.
The neurobiological imperative to maintain a balance between internal structures and external reality fuels this struggle for control, which contributes to making the contact zone a place of intractable conflict.