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arXiv · 2208.02818

Common Synaptic Input, Synergies, and Size Principle: Control of Spinal Motor Neurons for Movement Generation

François Hug·Simon Avrillon·Jaime Ibáñez·Dario Farina
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Abstract

Understanding how movement is controlled by the central nervous system remains a major challenge, with ongoing debate about basic features underlying this control. In this review, we introduce a new conceptual framework for the distribution of common input to spinal motor neurons. Specifically, this framework is based on the following assumptions: 1) motor neurons are grouped into functional groups (clusters) based on the common inputs they receive; 2) clusters may significantly differ from the classical definition of motor neuron pools, such that they may span across muscles and/or involve only a portion of a muscle; 3) clusters represent functional modules used by the central nervous system to reduce the dimensionality of the control; and 4) selective volitional control of single motor neurons within a cluster receiving common inputs cannot be achieved. We discuss this framework and its underlying theoretical and experimental evidence.

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François Hug, Simon Avrillon, Jaime Ibáñez, Dario Farina. 2022-07-27. Common Synaptic Input, Synergies, and Size Principle: Control of Spinal Motor Neurons for Movement Generation. https://arxiv.org/abs/2208.02818

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