Muscle afferents and the neural dynamics of limb position and velocity sensations.

Today muscle spindles are thought to be the primary receptor responsible for limb position and velocity. A mathematical model describing the muscle spindle's complex dynamical behavior was developed recently by Hasan. Other researchers have observed neuronal firing in the cortex of primates when muscles surrounding a joint have been passively stretched by joint movement. The purpose of this paper is to apply the muscle spindle model to a "two-muscle joint" and quantitate the resultant firing rates for various joint positions and velocities. With this information insights into the required neuronal dynamics for extracting position and velocity information from muscle spindles can be gained.