Suppose a muscle is contracting too much, so we need a reflex to stop it from contracting too much.

Contraction of a muscle causes the muscle spindle to go slack, hence the Ia axons and II-axons do not fire action potentials. The Ib axon synapses with the alpha motor neuron via an inhibitory interneuron so that the muscle is stopped from contracting. But what happens to the gamma motor neuron? Is it also inhibited just like the alpha motor neuron is inhibited? If indeed, it is inhibited, is it the Ib axon that inhibits it? I mean if it was not inhibited, then it would activate the Ia axon and the II axon which would activate the alpha motor neuron. As a result, there would be conflicting messages sent to the alpha motor neuron (excitatory from Ia and II and inhibitory from Ib).

During stretching of a muscle, for example, during the patellar reflex, the Ia axon and II axon are activated, which activate the alpha motor neuron as well as the gamma motor neuron to get contraction and contraction over and over again until the muscle returns to its set point.

During stretching, is only the muscle spindle active?

During contraction, is only the Golgi-tendon-organ active?



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