Meeting Abstract

P3-102   -   Effects of Hindlimb Nerve Reinnervation on Landing Performance in Rhinella marina. Duman, A*; Azizi, E; University of California Irvine; University of California Irvine aduman@uci.edu

Terrestrial animals can move maintain a high degree of coordination and economy across a wide range of surfaces conditions (e.g. sand, mud, rock). To move effectively across a various terrain and unpredictable conditions animals rely on a contribution of passive mechanical properties and actively mediated neuromuscular responses to keep from slipping up and missing out on dinner or becoming dinner. The cane toad, Rhinella marina, is an ideal model of studying locomotor control as they hop great distances, propel themselves with the hindlimbs and land on their forelimbs separating muscles that act as motors from those that act as breaks, and previous work has illustrated the importance of hindlimb proprioception on their coordinated landing behavior. To understand how proprioception may be informing landing behavior we performed a stretch reflex ablation by bilaterally transecting the sciatic nerve just proximal to the knee and allowing sufficient time for the motor neurons to reinnervate. With this perturbation, the cane toads (N = 10) could hop normally but lack proprioceptive feedback from the length changes of the hindlimb muscles during takeoff. Preliminary results show a sustained loss in the function of the stretch reflex at the ankle; however, they also indicate little change in landing behavior due to the loss of the stretch reflex in the distal hindlimb.