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PubMed · 1620137

Cortical mechanisms mediating asterixis.

J Artieda·J Muruzabal·R Larumbe·C García de Casasola·J A Obeso
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Abstract

We describe a patient with chronic renal failure who suffered multifocal action-induced jerks. Electromyography (EMG) recorded the typical silence of asterixis. Back-averaging the EEG activity preceding the EMG silent periods in the forearm showed a biphasic wave antedating the asterixis by 23 ms. Somatosensory evoked potentials (SEPs) after median nerve stimulation were pathologically enlarged on both hemispheres. Brain-mapping of the biphasic wave preceding asterixis and the giant SEPs indicated a common origin in the sensorimotor cortex. This observation provides further documentation of a cortical origin for some types of asterixis in humans.

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Brain MappingCerebral CortexElectroencephalographyElectromyographyEvoked Potentials, SomatosensoryFemaleHumansKidney Failure, ChronicMiddle AgedMotor CortexMyoclonusNeuromuscular DiseasesPostureReaction TimeSignal Processing, Computer-AssistedSomatosensory CortexCase ReportsJournal Article

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J Artieda, J Muruzabal, R Larumbe, C García de Casasola, J A Obeso. 1992. Cortical mechanisms mediating asterixis.. https://doi.org/10.1002/mds.870070304

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