Title: Perturbation Dependent Homolateral Coordination: ​ A Role for Central Proprioceptive Processing

Speaker: Dr. Turgay Akay

Date/Time: Tuesday april 14th 9:30am-10:30am

Synopsis​: A central goal in motor control is to understand how the nervous system transforms sensory input into spatially accurate motor output. Terrestrial legged locomotion is an ideal model because it is rhythmic, naturally occurring, and supports robust data collection. All legged animals must place their feet precisely to maintain balance, especially on uneven terrain.

In bipeds this relies largely on vision, but quadrupeds cannot depend solely on visual input to guide hind limbs outside the visual field. We asked whether proprioceptive feedback directs hind limb placement during swing in mice. Using genetic manipulations and in vivo behavioral analyses, we found that steady treadmill locomotion produces consistent hind limb placement with little reliance on muscle spindle feedback. However, perturbations evoke forelimb‑guided placement, a coordination lost without sensory feedback from the muscle spindles. Chemogenetic silencing shows this coupling requires supraspinal processing in the cuneate nucleus.​