Ever made a decision you later regretted?

Lots of people have. Whether it's choosing the kitchen's paint color, blurting out harmful words, or buying a "money pit" house, many of us can look back and wish we'd done things differently, though we may have learned or grown from the experience.

That "would-a, could-a, should-a" emotion apparently registers on your brain. New research traces regret to the brain's medial orbitofrontal cortex.

The finding comes from scientists including Professor Raymond Dolan, MD, FRCPsych, FMedSci, FRCP. Dolan heads the Wellcome Department of Imaging Neuroscience at University College London.

The researchers show that regret is influenced by personal responsibility and is different from disappointment. Their study appears in Nature Neuroscience.

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Researching Regret

Dolan and colleagues studied regret in 15 healthy people. Using a computer game, participants made "investments" with various risks and payoffs. Meanwhile, they got brain scans.

Occasionally participants followed choices made by a computer in which they were able to see outcomes.

The researchers also deliberately triggered regret in participants by showing them that they could have made better choices in games where the subjects selected which gamble to play.

Regret affected participants' strategy. They weighed their options, avoiding those that they thought would bring more regret.

That didn't always work. As regret deepened, so did participants' efforts to escape the emotion by making better choices.

When participants felt or acted upon regret, the brain scans showed activity in the medial feel badly about -- but not responsible for -- an unexpectedly negative outcome, write Dolan and colleagues.orbitofrontal cortex and the amygdala, where emotions are processed.

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Is It Regret or Disappointment?

Regret hinges on a sense of personal responsibility, the researchers note.

In regret, people feel badly because they didn't make the best choice. In disappointment, they

In some games, the computer made all the choices. When those games turned out poorly, the brain's regret center wasn't active, write the researchers.

By Miranda Hitti, reviewed by Brunilda Nazario, MD

SOURCES: Coricelli, G. Nature Neuroscience, Aug. 7, 2005; advance online edition. WebMD Medical News: "We Humans Know Fear When We See It." News release, Nature Research Journals.