This stretching deforms the terminals of the Ib afferent axon, opening stretch-sensitive cation channels.
[4][7] The Ib sensory feedback generates stretch reflexes and supraspinal responses which control muscle contraction.
Ib afferents synapse with interneurons in the spinal cord that also project to the brain cerebellum and cerebral cortex.
Tendon organs signal muscle force through the entire physiological range, not only at high strain.
[citation needed] However, the underlying premise was shown to be incorrect by James Houk and Elwood Henneman in 1967.