Gamma Motor Neuron Definition


Gamma Motor Neuron: Motor neurons which activate the contractile regions of intrafusal muscle fibers, thus adjusting the sensitivity of the muscle spindles to stretch. Gamma motor neurons may be “static” or “dynamic” according to which aspect of responsiveness (or which fiber types) they regulate. The alpha and gamma motor neurons are often activated together (alpha gamma coactivation) which allows the spindles to contribute to the control of movement trajectories despite changes in muscle length.

Synonym: gamma-efferent motor neuron, fusimotor neuron.