Through vision, audition, somatosensation, and the other senses, we perceive the world and our relationship to it. Much of the brain and nervous system is devoted to the processing of sensory input, in order to construct detailed representations of the external environment. In most cases, however, cognitive processing occurs to make actions adaptive and appropriate for the particular situation. Sometimes the pathway from sensation to action is direct, as in a reflex. This theory has been rejected in favor of one that explains the reflex with free nerve endings.Sensory receptors provide information about the environment, which is then used to produce action to change the environment. It was once believed that Golgi tendon organs were responsible for the clasp-knife reflex observed in spinal cord-injured patients. The ascending or afferent pathways to the cerebellum are the dorsal and ventral spinocerebellar tracts and are involved in the cerebellar regulation of movement. One of the main spinal reflexes receiving an input from the Ib afferent is the autogenic inhibition reflex, which is involved with the regulation of the force profile of on-going muscle contractions. The Ib afferent axon synapses with interneurons within the spinal cord and also relays information to the brain. Specifically, it is postulated that because a Golgi tendon organ exists in serial connection with muscle fibers, it can measure the tension that each muscle contraction builds up. This sensory feedback plays an important role in spinal reflexes and in the central control of muscle contraction. The action potential frequency signals the force being developed within the muscle. As a result, the axon is depolarized and fires nerve impulses up to the central nervous system via the spinal cord. This stretching deforms the terminals of the Ib afferent axon, opening stretch-sensitive cation channels. One or more nerve fibres perforate the side of the capsule and lose their medullary sheaths the axis-cylinders subdivide and end between the tendon fibers in irregular disks or varicosities (see figure).ĭuring muscle contraction the strands of collagen are stretched as the muscle shortens. Each neurotendinous spindle is enclosed in a fibrous capsule which contains a number of enlarged tendon fasciculi (intrafusal fasciculi). The Ib afferent axon is a large diameter, myelinated axon. Each tendon organ is innervated by a single afferent type Ib sensory fiber that branches and terminates as spiral endings around the collagen strands. The body of the organ is made up of strands of collagen that are connected at one end to the muscle fibres and at the other merge into the tendon proper. The Golgi organ should not be confused with the Golgi Apparatus, which is an organelle in the eukaryotic cell, or the Golgi stain, which is an histologic stain for neuron cell bodies. The Golgi organ (also called Golgi tendon organ, neurotendinous organ or neurotendinous spindle), is a proprioceptive sensory receptor organ that is located at the insertion of skeletal muscle fibres into the tendons of skeletal muscle. List of terms related to Golgi tendon organ Risk calculators and risk factors for Golgi tendon organĬauses & Risk Factors for Golgi tendon organĭiagnostic studies for Golgi tendon organ US National Guidelines Clearinghouse on Golgi tendon organĭirections to Hospitals Treating Golgi tendon organ Ongoing Trials on Golgi tendon organ at Clinical Ĭlinical Trials on Golgi tendon organ at Google Most cited articles on Golgi tendon organĪrticles on Golgi tendon organ in N Eng J Med, Lancet, BMJĬochrane Collaboration on Golgi tendon organ Most recent articles on Golgi tendon organ
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