The finding adds a significant piece to the puzzle of how the brain is wired to make judgments, perhaps even moral judgments, about the outside world, said the researchers. The findings may also have implications for understanding a number of neurological disorders, said the scientists. Damage to the area the researchers studied -- called the posterior cingulate cortex -- has been linked to cognitive decline in Alzheimer's disease, as well as pathologies of stroke, obsessive-compulsive disorder, schizophrenia and spatial disorientation.
The researchers, led by Michael Platt, Ph.D., Duke University Medical Center assistant professor of neurobiology, published their findings in the Dec. 4, 2003, issue of the journal Neuron. Other authors on the paper were joint lead authors Allison McCoy of Duke and Justin Crowley, Ph.D., of Carnegie Mellon University; and Golnaz Haghighian and Heather Dean of Duke.
"Even though the posterior cingulate cortex is a large structure in the brain that is easily identifiable in all mammals, including humans, almost nothing was known about what it might do," said Platt. "Anatomical studies show that it is kind of a nexus of brain circuitry involved in motivational or emotional inputs from the limbic system. And it is strongly connected to structures involved in making decisions and generating responses. So, we theorized that it seemed to be important for somehow putting together the costs and benefits associated with different options in an animal's environment."
The researchers chose to study the role of the posterior cingulate cortex in making decisions about eye movement, because the visual system and the neural control of the eye muscles is ve
Contact: Dennis Meredith
Duke University Medical Center