Evolving Toward Addiction

Harvard evolutionary psychologist Deidre Barrett says humans aren't immune from instinct. What developed from behaviors necessary to survive hundreds or thousands of years ago still govern today. But now those instinctive reactions to modern "supernormal stimuli" are at the root of overindulgence and behavioral addictions.

Audio: BBC, PRI & WBUR's Here & Now 3/17/10, Host: Robin Young.