When Bigotry Isn't Caused By Pure Animus Toward "The Other"

Donald Trump has hit a nerve, literally. There is no excuse for his Know-Nothing, fact-free attacks on immigrants. But why are some people so receptive to his rhetoric, especially   given the fact that America is a "Nation of Immigrants"?

One reason might be that our brains are hard-wired to find listening to a foreign language we don't understand to be extremely annoying. Check out this write up of a study that combined linguistics and brain science (The Brain Is A Prediction Machine):

Traditionally, it was thought that our brains always process the world around us from the “bottom up” — when we hear someone speak, our auditory cortex first processes the sounds, and then other areas in the brain put those sounds together into words and then sentences and larger discourse units. From here, we derive meaning and an understanding of the content of what is said to us.
However, in recent years, many neuroscientists have shifted to a “top-down” view of the brain, which they now see as a “prediction machine”: We are constantly anticipating events in the world around us so that we can respond to them quickly and accurately. For example, we can predict words and sounds based on context — and our brain takes advantage of this. For instance, when we hear “Grass is …” we can easily predict “green.”
What’s less understood is how this predictability might affect the speaker’s brain or even the interaction between speakers and listeners.

Notice how this jibes with what Latinos tell Gallup about their experiences with discrimination:

One factor that may explain the gap in discrimination between native-born and foreign-born Hispanics is language. The poll included interviews with Hispanics in both English and Spanish, with those born outside the U.S. much more likely to be interviewed in Spanish than native-born Hispanics. In turn, the analysis shows that reports of discrimination are much higher among foreign-born Hispanics who are interviewed in Spanish than those interviewed in English. This indicates that language, in addition to ethnicity, may be a key factor in Hispanics' reports of discrimination and in any actual discrimination that occurs.

Trying to do something and failing is really annoying! That's what our brain is going through every time we hear someone speaking a language we don't understand. 

What happens next? We come up with a story about how understanding these people is totally not necessary. If our unconscious mind is a prediction machine, our conscious brain is A Rationalization Machine. Michael Schermer's hypothesis is: "that humans form beliefs first and then seek evidence consistent with those beliefs".

If that's the case, overcoming prejudice may not be a job for arguments, but rather exposing people to diversity from a young age so that hearing or seeing someone different is less annoying, removing the need for the narrative of prejudice that follows from the feeling.