A possible partitioning of segmental muscle stretch reflex into incompletely de-coupled parallel loops.

Based on previous investigations on focused signal transmission through the muscle stretch reflex system, a model is presented suggesting that different muscle areas (especially in large complex muscles such as the triceps surae muscle) may be regulated rather independently with respect to certain internal state variables, particularly internal length. Since the parallel localized reflex loops necessary for such local control tasks are inevitably coupled peripherally through the muscle and connective tissues, compensatory de-coupling elements would be required to reestablish at least partial independence. Whether and how this can be achieved at the level of spinal neuronal circuitry is investigated in connection with a discussion of the advantages of partially de-coupled reflex loops.