A muscle fiber that is small, within each muscle spindle 2 to 12 are located within them. The intrafusal fibers are sensitive to muscle tension and stretching and the stretch receptors which they are connected to.

INTRAFUSAL FIBER: "Intrafusal Fiber compare extra-fusai, fiber and is a small muscle fiber"
Cite this page: N., Pam M.S., "INTRAFUSAL FIBER," in, May 11, 2013, (accessed October 18, 2021).