Decisions and desire.

When we make decisions, we're not always in charge. One moment we hotheadedly let our emotions get the better of us; the next, we're paralyzed by uncertainty. Then we'll pull a brilliant decision out of thin air--and wonder how we did it. Though we may have no idea how decision making happens, neuroscientists peering deep into our brains are beginning to get the picture. What they're finding may not be what you want to hear, but it's worth listening. We have dog brains, basically, with human cortexes stuck on top. By watching the brain in action as it deliberates and decides, neuroscientists are finding that not a second goes by that our animal brains aren't conferring with our modern cortexes to influence their choices. Scientists have discovered, for example, that the "reward" circuits in the brain that activate in response to cocaine, chocolate, sex, and music also find pleasure in the mere anticipation of making money--or getting revenge. And the "aversion" circuits that react to the threat of physical pain also respond with disgust when we feel cheated by a partner. In this article, HBR senior editor Gardiner Morse describes the experiments that illuminate the aggressive participation of our emotion-driven animal brains in decision making. This research also shows that our emotional brains needn't always operate beneath our radar. While our dog brains sometimes hijack our higher cognitive functions to drive bad, or at least illogical, decisions, they play an important part in rational decision making as well. The more we understand about how we make decisions, the better we can manage them.