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PubMed · 57051

Latencies of evoked potentials to flicker and to pattern speedily estimated by simultaneous method.

D Regan
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Abstract

This note describes a method for rapidly measuring the latency of a steady-state visual evoked potential (EP). Three sinewaves of different frequencies (F1, F2 and F3 c/sec) are summed, and the resulting waveform modulates either light intensity (for flicker stimulation) or spatial contrast (for pattern stimulation). Three evoked potentials of frequencies F1, F2 and F3 c/sec respectively are stimultaneously recorded by running three Fourier analysers in parallel. The outputs of the three analysers are presented in a single polar plot so as directly to display the three values of EP amplitude and phase. Practical methods for generating the pattern and flicker stimuli are described.

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Computers, AnalogElectroencephalographyEvoked PotentialsHumansPattern Recognition, VisualPhotic StimulationReaction TimeTime FactorsVisual PerceptionJournal Article

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BibTeXRIS

D Regan. 1976. Latencies of evoked potentials to flicker and to pattern speedily estimated by simultaneous method.. https://doi.org/10.1016/0013-4694(76)90140-1

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Computers, Analog↗