Interactions Between Afferent Pathways and Pattern Generators

Afferent input has been shown to play a major role in our capacity to reactivate spinal circuits that generate coordinated rhythmic flexion and extension of the limb muscles in spinal cord injury patients. Our studies revealed that stimulation of sacrocaudal afferents (SCA) is a potent means for activating the locomotor central pattern generators (CPGs) in rodents spinal cords that lack the descending control from the brain. These studies showed that capacity of SCA to induce the locomotor rhythm depends on activation of sacrocaudal neurons the crossed and uncrossed projections of which, ascend through the ventral and lateral white matter funiculi (VF,VLF, LF, and DLF) to the limb innervating segments of the cord. The project examines the axonal projections, spatial distribution, organization and physiological properties of these sacrocaudal neurons and evaluates their role in the generation of afferent induced rhythmicity in the spinal cord. The studies are performed in collaboration with Dr. L. Anglister and E. Finkel, from our department and with Drs. M.J. O'Donovan and G. Z Mentis from the NINDS, NIH, USA. (Anglister et al. 2008, Lev-Tov and O'Donovan 2009, Lev-Tov et al. 2010, Etlin et. al. 2010)