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

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 an attempt to purge a toxin.
Both were triggered at least partly by your prefrontal cortex and your temporal lobes — and both would have occurred had you smelled a piece of food gone bad.
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http://www.time.com/time/health/article/0,8599,2104161,00.html