Neuromechanical phase lag predicts material and neural control properties in Caenorhabditis elegans

Abstract

In all animals, the successful orchestration of motor programs hinges on appropriate coupling between components of the system, from neural circuit dynamics, through muscles and body properties to the physical environment. We study this coupling in undulatory locomotion, with a view to better understanding the relative roles of central and reflex-driven control. We ask how the coupling between neural control and body mechanics is affected by sensory inputs during undulatory locomotion in C. elegans. To address this question, we use a biomechanical simulation framework, within which we separately model feed forward and feedback controlled undulations. We characterize neuromechanical phase lag and locomotion speed using body stiffness as a control parameter. We show that sensory entrainment can suppress neuromechanical phase lag, that would otherwise emerge under centrally generated feed forward control.