People come to a conclusion, sometimes by informed means, sometimes not, but however we come to it, we generally stick to that conclusion, for better or worse. Once we've reached that conclusion though, we become very bad scientists. We discard data that doesn't fit with our conclusion, or if we can't discard it, attempt to minimize its significance and promote things that do fit our conclusions as more important.

The media panders to their audience, constantly surveying their audience and reactions, and serving up more and more of the news that we're already predisposed to the news we want to hear. Once a certain capture rate has occurred, the news that people choose begins shaping opinions.

Newsroom parodies this somewhat (disclaimer, I love the show, even though its politics disagree with my own), proclaiming that the Fairness Doctrine was unnecessary, and you can deliver hard-hitting news fairly and accurately without it (which may be a true assumption, maybe not), but then they proceed to deliver extremely biased news coverage that is extremely colored by their own politics and beliefs, presented as intellectualism because we're supposed to get the idea that Will McAvoy is the smartest man in whatever room he's in, so all his opinions are informed by sheer fact and wisdom, so we should believe that whatever he says is true because of that.

Despite that coloring, we see in every off-air scene that he's well informed, but terrible at drawing pragmatic conclusions from a given set of facts, belying that the central theme of the show is even possible with the cast of characters as presented.

Back on topic, because I'm rambling terribly, but the brain rewards itself when it finds facts that agree with its pre-existing beliefs. A chemical 'high five' to reaffirm how right it already was, and to reinforce that it made the right decision before, and now the rest of the world is catching up. I don't know that this can be fixed, but I think that the surest way to mitigate it is to disallow it from becoming too set in its ways, to keep it slightly off-guard, and in a constant state of discomfort.

This might kill us in some other way, and it's possible that the brain will just refuse to allow this, or that we'll all become blathering idiots as a result, but i's at least a step in the right direction of preventing a vicious cycle of arbitrary self-affirmation.