Where choices happen
Different decisions are made in different areas of the brain’s frontal lobes
Making tough choices won’t get any easier, but scientists have discovered that different types of decisions are made in different areas of the brain’s frontal lobes. Abstract decisions are made toward the front of the lobes and concrete decisions are made toward the back, researchers report in a study published online March 1 in Nature Neuroscience. The find could help scientists understand the organization of the frontal lobes and processes like learning and reasoning, the researchers say.
Abstract decisions involve choosing between different categories of options, like deciding whether to send an e-mail or call on the phone instead. Concrete decisions involve translating thoughts into action, like deciding to hit a key to send the e-mail.
The brain’s frontal lobes, which sit behind the forehead, “allow us to use what we know about the world to guide our decision making,” says neuroscientist and study coauthor David Badre of Brown University in Providence, R.I.
Previous work has shown that neurons fire in different areas of the frontal lobes as different types of decisions are made. That led researchers to think the frontal lobes could be organized into areas with different decision-making tasks. But the new research “provides the first direct evidence of this,” comments neuroscientist Jean-Claude Dreher of the Institute for Cognitive Sciences at the Centre National de la Recherche Scientifique in Bron, France.
Badre and his colleagues investigated decision making in people who had sustained damage to different areas of the frontal lobes. The study participants, whose brain injuries came from strokes, were asked to make a series of decisions ranging from simple to more complex.
Participants with damage toward the front end of the frontal lobes were more likely to be impaired at making abstract decisions, while people with damage to the tail end of the lobes had difficulty making concrete decisions, the scientists found.
The strokes could have caused damage to other areas of the brain as well, Dreher notes.
“Undoubtedly,” Badre concedes, but he says that the correlation is strong.
In addition to providing information about brain functioning, Badre notes, the find “could also help us to diagnose behavioral problems in people with different types of brain injury.”
