01/10/2012 09:17 am ET Updated Jan 10, 2012

Prejudice In The Brain: Can You Break Your Biased Habits? (VIDEO)

Hi everyone. Cara Santa Maria here.

How do we become who we are, as people, with all of our quirks, our interests, our emotions and our flaws? And how do we choose who to call a friend? An enemy?

Well, as human beings we are constantly categorizing the world in an effort to identify threats. Evolutionary psychologists hypothesize that early Homo sapiens rarely came into contact with anyone who looked, sounded, or dressed differently.

One of the biggest problems with prejudice in modern society is that we often perceive people as being threatening even if they pose no real danger. So something that evolved as a protective mechanism in tribal society--when we didn't often encounter "outsiders"--has become highly maladaptive. And left unchecked, it can fuel discrimination, fear, and downright hatred and violence.

We know that culture poisons the brain with all types of “isms”: racism, sexism, ageism. Those are the obvious ones, but there are other implicit biases we may not even realize we have. For example, a recent study showed that atheists are deemed about as trustworthy as rapists. Do you find yourself thinking that someone is less moral than you are because of their particular religious beliefs, or lack thereof?

We've spent years studying prejudice behaviorally, but recent advances allow us to physically measure its underlying neural mechanisms.

In one neuroimaging study, researchers found that when people looked at pictures of other people, their medial prefrontal cortex was activated. But, when looking at pictures of social outcasts, like drug addicts, this brain area was silent, just like when people looked at pictures of objects. So while people may consciously see members of extreme social out-groups as people, the brain processes them as something less than, effectively dehumanizing them.

In another study, quick reactions to people of a different race generally activated the amygdala, an older, deep brain structure associated with fear. Luckily, we don't usually rely on our animal instincts in our day-to-day lives. Given even the tiniest amount of processing time, higher brain structures like the anterior cingulate and the dorsolateral prefrontal cortex can quiet the fear response of our more primal brain regions. That's why most of us, even though we have these implicit prejudices, don't act out violently toward people who aren't like us.

But for those who do, there is hope. It seems we can retrain the biased brain, according to prejudice researcher Patricia Devine. But, these three steps have to take place: First, we need to become aware of our implicit biases. Next, we must be concerned about the consequences of those biases. Last, we should learn to replace those biased responses with non-prejudiced ones--ones that more closely match the values we consciously believe we hold.

And come on. When it comes to race, only 0.01% of our entire genome affects how we look. According to geneticist Craig Venter, "Race is a social concept. Not a scientific one."

Can you break the biased habits of your brain? Tell me your thoughts on Twitter, Facebook, or right here on The Huffington Post. Come on, talk nerdy to me!

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