The visually evoked cortical potential : stimulus effects and interactions

UNCG Author/Contributor (non-UNCG co-authors, if there are any, appear on document)
Constance DePew Suitt (Creator)
The University of North Carolina at Greensboro (UNCG )
Web Site:
Robert G. Eason

Abstract: The purpose of this investigation was to obtain parametric data on the effects and interactions of stimulus variables (intensity and size), retinal locus of stimulation and background adaptation level on the visually evoked cortical potential. The subjects were graduate students and faculty with no gross visual defects. The potential was evoked by white light flashes and averaged with a Mnemotron CAT. Three amplitude components of the evoked potential were measured for each of the subjects, over four replications, averaged, and an analysis of variance was performed on the data. The amplitude of the evoked potential was found to vary significantly as a function of site of stimulation (p < .01), intensity of the stimulus (p <.01), and size of the stimulus (p <.05). The background variable was not found to effect a significant change. Three significant first-order interactions were found: background by site (p <.05), background by size (p <.01), and site by size (p <.05). An important implication of the results is that consideration should be given to the magnitude of the physical parameters of the visual stimulus, and to their interactions, when interpreting the results of experiments dealing with relationships between visually evoked potentials and behavioral variables.

Additional Information

Language: English
Date: 1971
Visual evoked response
Evoked potentials (Electrophysiology)

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