Grant: Operating Grant

Some of the most fundamental movements essential for survival, like breathing, chewing and walking are repetitive and rhythmic in nature. These movements are secured by neuronal networks that are similar in their organization and in their properties. One of the most important properties of these networks is the ability to generate a rhythmic motor command. In this project, we examine the cellular mechanisms underlying this property of "rhythmogenesis" in the masticatory system. Our previous results suggest that glial cells may be critical to enable the neurons of this system to generate a rhythmic activity by controlling the ionic composition of the extracellular fluid. Here we propose to dissect the mechanisms involved in this interaction and to explore how the pattern of activity generated by the "rhythmogenic" neurons is transmitted in a coordonated manner to the motoneurons controlling the various muscles involved in the behavior. We will also examine how the rhythmogenic neurons use sensry information from the oral region to adjust the pattern of the movements produced according to the prevailing conditions. Many of the brain functions are based on the ability to generate a rhythm and we expect these findings to be of application to many other behaviors besides chewing.