Why We Love to Loathe John Edwards: It's Science

http://www.time.com/time/health/article/0,8599,2104161,00.html

John Edwards is the putrefied meat of the American political system — literally, as far as your brain is concerned. Think about Edwards for a moment — the perfect hair, the honey voice, the oleaginous smile. Your lip curled ever so slightly, didn't it? A teensy bit of bile may have risen in your throat. The lip curl is a threat display, the bile is an attempt to purge a toxin. Both were triggered at least partly by your prefrontal cortex and your temporal lobes — and both would have also occurred if you'd smelled a piece of food gone bad.

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There are a lot of things that make the ex-senator the pariah he is, and the brain is indeed one of the biggest players. It was only in the last decade or so, with the widespread use of functional magnetic imaging (fMRI), that neurologists discovered the overlapping circuitry that governs morality and disgust. In one study conducted in many parts of the world, pairs of subjects are given a quantity of cash to share — say $100 — with one of them getting to decide how the sum will be split and the other having the right to accept or reject the offer. If the deal is accepted, they both get the cash; if it's rejected, they both get nothing.

On average, subjects turn down any proposed division that offers them less than 43% of the pot — meaning they walk away from a free $43 simply because the other guy is getting $57. And when the subjects who reject the deal are scanned by fMRIs, their brains show pronounced activity in the disgust regions.

"There is literal disgust and moral disgust, and the two overlap," says Jonathan Haidt, professor of psychology at the University of Virginia. "Betrayal, hypocrisy, certain kinds of baseness trigger the brain's moral response."