In their study on rats, they demonstrated that they could distinguish in unprecedented detail the patterns of brain activity -- including fleeting changes in communication among brain structures -- in awake animals, as they fall sleep and as they transition among different sleep stages.
The study is important, not only for its insight into the sleep process, but because neurobiologists have strong evidence that memory consolidation occurs during sleep, said the researchers.
More generally, they believe that their new analytical technique will enable unprecedented insights into function of both the healthy brain and those afflicted with neurological disease. Such insights could lead to new understanding and treatment if diseases including epilepsy, Alzheimer's disease and schizophrenia, they said.
Led by neurobiologist Dr. Miguel Nicolelis, M.D., Ph.D., the researchers published their findings in the December 8, 2004, Journal of Neuroscience. Nicolelis is professor of neurobiology and co-director of Duke's Center for Neuroengineering. Other co-authors were Damien Gervasoni, Shih-Chieh Lin, Sidarta Ribeiro, Ernesto Soares and Janaina Pantoja. The research was sponsored by the National Institutes of Health.
In their studies, Nicolelis and his colleagues implanted the microelectrodes, smaller than the diameter of a human hair, into regions of the brain responsible for a range of functions -- including sensory processing, motor function and memory formation. They then recorded and analyzed the electrical signals from the rats as the animals went through several days of sleep-wake cycling. Their analysis could detect activity patterns that marked waking, deep "slow wave"
Contact: Dennis Meredith
Duke University Medical Center