Modeling of dynamic controls in the frog wiping reflex: Force-field level controls

Abstract

We compare free-limb kinematics in deafferented and afferented spinal frogs and use a dynamic model to generate model kinematics driven by isometric force-field patterns from the same animals for comparison. Afferented paths in simulation and experiment agree over 50% of their extent. Results suggest that frogs use sensory information to construct force-fields that minimize the need for eccentric muscle contractions during movement, but such eccentric contractions in deafferented frogs compensate interaction torques. The simulation data support movement construction as an adjusted combination of force-field primitives and demonstrate the importance of non-isometric properties of the force-field primitive. © 2001 Elsevier Science B.V. All rights reserved.