Grant: Project Grant

In order for mammals to walk a complex pattern of muscle activation is required. For more than a century it has been known that the timing and pattern of stepping movements in mammals are generated by neural networks known as central pattern generators (CPGs) which are comprised of multiple interneuron cell types located entirely within the spinal cord. A genetic approach has recently been successful in identifying several populations of spinal neurons that make up this neural network as well as the specific role they play during stepping. In spite of this progress the neurons responsible for generating the locomotor rhythm have yet to be identified. Recently my laboratory has devised a novel experimental protocol which allows us to visualize neuronal activity in spinal neurons during locomotor activity. We have used this approach to identify a population of neurons that possess many properties thought to be essential for locomotor rhythm generation. In the proposed experiments we will use this approach as well as a series of electrophysiological, anatomical, and molecular techniques to characterize these neurons and determine whether they are necessary and sufficient for the generation of locomotor activity. These studies will provide key insight into the structure and mechanism of function of the locomotor CPG and will also assist those developing strategies aimed at enhancing recovery of motor function for spinal cord injured patients.