NROC64H3 Chapter Notes - Chapter 5: Muscle Spindle, Pocketknife, Type Ia Sensory Fiber
Document Summary
Proprioception: mechanoreceps that give us info about position and movements of limbs etc. 2 kinds of proprioceps in voluntary muscles: muscle spindles: respond to muscle length and rate of change of length, golgi tendon organs: signal muscle tension, force. Spindles are parallel w/ main contractile elements in muscle. Their stretching is measure of degree of stretch of muscle. Tendon organs are in muscle tendons, are in series w/ contractile elements/load. ****don"t understand: consequently, when a muscle contracts the tendon organs are stimulated by the extra tension, but the activity of the sensory elements in the spindles is reduced as they are less stretched******** Found in almost all striated muscles of body. Each has a fluid filled spindle capsule 2-4mm long; ends are attached to exterior sheaths of neighboring muscle fibres. Inside spindle has intrafusal fibres; each has contractile ends; area in middle not contractile but has nuclei.
