Date: Wednesday, May 11, 2016
Time: 4:00 pm-5:00 pm, followed by reception
Speaker: Maiken Nedergaard, M.D., Ph.D.
Affiliation: Professor/Co-Director, University of Rochester/University of Copenhagen
Host: Mriganka Sur, Ph.D., FRS

Talk title: Ionostatic control of the sleep-wake cycle

 Abstract: The concerted release of neuromodulators, including norepinephrine, acetylcholine, histamine, dopamine, and orexin mediates arousal. All of these neuromodulators individually alter the membrane properties, spiking activity, and intracellular signaling pathways of subpopulations of neurons and glia, but how they implement the striking stereotypic patterns of EEG activity characterizing wakefulness versus sleep is not understood. We have in recent work found astrocytes play an unexpected important role in modulating the state of brain activity. In response to neuromodulators, astrocytes control the extracellular ion concentrations. In turn,  the  changes in extracellular K+, Ca2+, and Mg2+ appears to play a crucial role in shaping the EEG activity characteristic of  the sleep-wake cycle.