The paper, "Cooperative synchronized assemblies enhance orientation discrimination," by Vanderbilt professor of biomedical engineering A. B. Bonds with graduate students Jason Samonds and Heather A. Brown and research associate John D. Allison provides some of the first solid evidence that the exact timing of the tiny electrical spikes produced by neurons plays an important role in brain functioning. Since the discovery of alpha waves in 1929, experts have known that neurons in different parts of the brain periodically coordinate their activity with their neighbors. Despite a variety of theories, however, scientists have not been able to determine whether this "neuronal synchrony" has a functional role or if it is just a by-product of the brain's electrical activity.
Until recently studies have focused on the firing rate of brain cells as the basic unit of information the bits and bytes used by our organic computer. The reason for this fixation was evidence that the firing rates of sensory neurons contain important information. For example, the higher the firing rate of the pain-sensing neurons in the back of your hand, the greater your brain's perception of pain in that location.
"We are exploring how information is represented by the brain," says A. B. Bonds, professor of biomedical engineering at Vanderbilt, who co-authored the new study with graduate students "One representation is the firing rate of individual nerve cells, but this does not acknowledge the intricate network structure of the brain, where each cell is connected with 1,000 other cells, on average. One wa
Contact: David F. Salisbury