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PubMed · 9442436

Phase information in visual evoked potentials.

E Micheli-Tzanakou·S Pavlopoulos
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Abstract

The Visual Evoked Potential (VEP) is an electrophysiological commonly used test in investigating various neurophysiological disorders. Through the years many methods have been developed, but there are not many objective criteria in distinguishing a normal VEP waveform from an abnormal. In this communication we use the phase characteristics of the power spectrum as a criterion of distinguishing normals and abnormals. From our analysis, it was shown that the phase spectrum of a VEP has a certain periodicity in the 0- to 40-Hz region. By studying these periodicities we were able to determine the range of the period that characterizes normal and abnormal populations and to establish an experimental method for objectively examining any kind of VEP waveforms.

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Alzheimer DiseaseArtifactsElectrophysiologyEvoked Potentials, VisualFourier AnalysisHumansNeurophysiologyObserver VariationPeriodicityPhotic StimulationSensitivity and SpecificitySignal Processing, Computer-AssistedSingle-Blind MethodJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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E Micheli-Tzanakou, S Pavlopoulos. 1997. Phase information in visual evoked potentials.. https://doi.org/10.1023/a%3A1022832520612

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