Relationship of visually evoked responses to patterning of stimuli and nature of perceptual discrimination, as a function of degree of dark adaptation

UNCG Author/Contributor (non-UNCG co-authors, if there are any, appear on document)
Barbara Ann Cook (Creator)
The University of North Carolina at Greensboro (UNCG )
Web Site:
M. Russell Harter

Abstract: The present study investigated the effects of stimulus- element size, dark-adaptation level, and the interaction of these variables on cortical evoked potentials and perceptual responses. Specifically, the study sought to define any systematic changes or relationships among these response measures as a function of the independent variables. Five subjects’ (Ss') cortical responses from three electrode placements, Oz, Oi, and O2, were recorded. By means of a haploscope, S could view with each eye separately a like display of a blank or checkerboard (checks subtending 20 or 60 min of arc) stimulus transparency. The right and left eye were presented the stimulus alternately by illumination of the display with back flashes. During the experimental session, the right, experimental eye (E eye) became dark adapted, while the left, control eye (C eye) was maintained at a constant level of adaptation. Evoked cortical responses and perceptual measures of absolute threshold and brightness-/or sharpness-match discriminations at prescribed regular intervals during each 15.0-minute session were obtained.

Additional Information

Language: English
Date: 1974
Visual evoked response
Visual perception

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