Biomaterial Database

Periodic leg movements of sleep (nocturnal myoclonus): an electrophysiological study. 1986

L R Wechsler, and J W Stakes, and B T Shahani, and N A Busis

Six patients with periodic leg movements of sleep (PLMS) were studied electrophysiologically. All patients had normal results on routine nerve conduction studies and electromyography. In 5 patients the blink reflex consisted of three components, and in 1 patient it consisted of four components, with two components being normal. The second component of their blink reflex did not habituate. Other abnormalities included long-latency responses in the extremities in 2 patients, release of H-reflexes from flexor hallucis brevis muscle in 2 patients, and an Hmax/Mmax ratio of 98% in 2 patients. One patient's median nerve somatosensory-evoked response had a markedly enlarged P22 wave. These electrophysiological abnormalities suggest a disorder of the central nervous system producing increased excitability of segmental reflexes. To produce increased excitability of both brainstem and spinal cord reflexes, the disorder must be operative at the pontine level or rostral to it. Since long-latency components of blink reflexes occurred in all our patients, this may be a helpful diagnostic test when PLMS is suspected.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D008875	Middle Aged	An adult aged 45 - 64 years.	Middle Age
D009207	Myoclonus	Involuntary shock-like contractions, irregular in rhythm and amplitude, followed by relaxation, of a muscle or a group of muscles. This condition may be a feature of some CENTRAL NERVOUS SYSTEM DISEASES; (e.g., EPILEPSY, MYOCLONIC). Nocturnal myoclonus is the principal feature of the NOCTURNAL MYOCLONUS SYNDROME. (From Adams et al., Principles of Neurology, 6th ed, pp102-3).	Myoclonus, Action,Myoclonus, Nocturnal,Myoclonus, Palatal,Polymyoclonus,Myoclonic Jerk,Myoclonic Jerking,Myoclonus Simplex,Myoclonus, Eyelid,Myoclonus, Intention,Myoclonus, Lower Extremity,Myoclonus, Oculopalatal,Myoclonus, Segmental,Myoclonus, Sleep,Myoclonus, Upper Extremity,Action Myoclonus,Extremity Myoclonus, Lower,Extremity Myoclonus, Upper,Eyelid Myoclonus,Intention Myoclonus,Jerk, Myoclonic,Jerking, Myoclonic,Jerks, Myoclonic,Lower Extremity Myoclonus,Myoclonic Jerks,Nocturnal Myoclonus,Oculopalatal Myoclonus,Palatal Myoclonus,Segmental Myoclonus,Simplex, Myoclonus,Sleep Myoclonus,Upper Extremity Myoclonus
D009420	Nervous System	The entire nerve apparatus, composed of a central part, the brain and spinal cord, and a peripheral part, the cranial and spinal nerves, autonomic ganglia, and plexuses. (Stedman, 26th ed)	Nervous Systems,System, Nervous,Systems, Nervous
D009431	Neural Conduction	The propagation of the NERVE IMPULSE along the nerve away from the site of an excitation stimulus.	Nerve Conduction,Conduction, Nerve,Conduction, Neural,Conductions, Nerve,Conductions, Neural,Nerve Conductions,Neural Conductions
D011930	Reaction Time	The time from the onset of a stimulus until a response is observed.	Response Latency,Response Speed,Response Time,Latency, Response,Reaction Times,Response Latencies,Response Times,Speed, Response,Speeds, Response
D012021	Reflex, Abnormal	An abnormal response to a stimulus applied to the sensory components of the nervous system. This may take the form of increased, decreased, or absent reflexes.	Hyperreflexia,Hyporeflexia,Abnormal Deep Tendon Reflex,Abnormal Reflex,Abnormal Reflexes,Bulbocavernosus Reflex, Decreased,Bulbocavernousus Reflex Absent,Hoffman's Reflex,Palmo-Mental Reflex,Reflex, Absent,Reflex, Acoustic, Abnormal,Reflex, Anal, Absent,Reflex, Anal, Decreased,Reflex, Ankle, Abnormal,Reflex, Ankle, Absent,Reflex, Ankle, Decreased,Reflex, Biceps, Abnormal,Reflex, Biceps, Absent,Reflex, Biceps, Decreased,Reflex, Corneal, Absent,Reflex, Corneal, Decreased,Reflex, Decreased,Reflex, Deep Tendon, Abnormal,Reflex, Deep Tendon, Absent,Reflex, Gag, Absent,Reflex, Gag, Decreased,Reflex, Knee, Abnormal,Reflex, Knee, Decreased,Reflex, Moro, Asymmetric,Reflex, Pendular,Reflex, Triceps, Abnormal,Reflex, Triceps, Absent,Reflex, Triceps, Decreased,Reflexes, Abnormal,Absent Reflex,Decreased Bulbocavernosus Reflex,Decreased Reflex,Palmo Mental Reflex,Pendular Reflex,Reflex Absent, Bulbocavernousus,Reflex, Decreased Bulbocavernosus,Reflex, Hoffman's,Reflex, Palmo-Mental
D012023	Reflex, Monosynaptic	A reflex in which the AFFERENT NEURONS synapse directly on the EFFERENT NEURONS, without any INTERCALATED NEURONS. (Lockard, Desk Reference for Neuroscience, 2nd ed.)	Monosynaptic Reflex
D001767	Blinking	Brief closing of the eyelids by involuntary normal periodic closing, as a protective measure, or by voluntary action.	Orbicularis Oculi Reflex,Reflex, Blink,Reflex, Corneal,Reflex, Orbicularis Oculi,Winking,Blink Reflexes,Corneal Reflexes,Orbicularis Oculi Reflexes,Blink Reflex,Reflexes, Blink,Reflexes, Orbicularis Oculi
D004576	Electromyography	Recording of the changes in electric potential of muscle by means of surface or needle electrodes.	Electromyogram,Surface Electromyography,Electromyograms,Electromyographies,Electromyographies, Surface,Electromyography, Surface,Surface Electromyographies