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Nerve conduction velocity is an important aspect of nerve conduction studies. It is the speed at which an electrochemical impulse propagates down a neural pathway. Conduction velocities are affected by a wide array of factors, including age, sex, and various medical conditions. Studies allow for better diagnoses of various neuropathies, especially demyelinating conditions as these conditions result in reduced or non-existent conduction velocities. ==Normal conduction velocities== Ultimately, conduction velocities are specific to each individual and depend largely on an axon's diameter and the degree to which that axon is myelinated, but the majority of 'normal' individuals fall within defined ranges. Nerve impulses are extremely fast, with some myelinated neurons conducting at speeds up to 120 m/s (432 km/h) Different sensory receptors are innervated by different types of nerve fibers. Proprioceptors are innervated by type Ia, Ib and II sensory fibers, mechanoreceptors by type II and III sensory fibers, and nociceptors and thermoreceptors by type III and IV sensory fibers. Normal impulses in peripheral nerves of the legs travel at 40–45 m/s, and 50–65 m/s in peripheral nerves of the arms.〔 Largely generalized, normal conduction velocities for any given nerve will be in the range of 50–60 m/s.〔(【引用サイトリンク】url=http://www.hopkinsmedicine.org/healthlibrary/test_procedures/neurological/nerve_conduction_velocity_ncv_92,P07657/ )〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「nerve conduction velocity」の詳細全文を読む スポンサード リンク
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