Researchers at the University of Minnesota Medical School and the Brain Sciences Center at the Minneapolis VA Medical Center have discovered a new way to assess how brain networks act together. Work funded by the MIND Institute (New Mexico) led Apostolos P. Georgopoulos, M.D., Ph.D., professor of neuroscience, neurology, and psychiatry, and collaborators to a novel way to assess the dynamic interactions of brain networks acting in synchrony, as reported in a recent issue of the Proceedings of the National Academy of Sciences. "This discovery will allow researchers to better evaluate the brain function of people with various diseases, such as Alzheimer's disease, and to monitor the effect of treatment, by assessing the status of the brain networks over time," Georgopoulos said. All behavior and cognition in the brain involves networks of nerves continuously interacting--these interactions occur on a millisecond by millisecond basis. Because the interactions in the brain happen so rapidly, it has been difficult to accurately assess them. Current methods of evaluation such as functional magnetic resonance imaging (fMRI) are too slow--they take seconds to detect activation. To better evaluate how the nerve networks in the brain communicate and interact with one another, researchers used magnetoencephalography (MEG) to record, with 1- millisecond temporal resolution, tiny magnetic fields from the brain during a short period of time. They studied this interaction in research subjects who looked at a spot of light. Georgopoulos used MEG data from 248 sensors to detect the changing interactions over time. The measurements they recorded represent the workings of tens of thousands of brain cells. The large amount of data recorded from each sensor was analyzed over time to view how large groups of active brain cells operate and interact simultaneously with each other in different parts of the brain.