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From spatial frequency contrast to edge preponderance: the differential modulation of early visual evoked potentials by natural scene stimuli

Published online by Cambridge University Press:  23 March 2011

BRUCE C. HANSEN ,
THEODORE JACQUES ,
AARON P. JOHNSON  and
DAVE ELLEMBERG
BRUCE C. HANSEN*
Affiliation:
Departments of Psychology and Neuroscience Program, Colgate University, Hamilton, New York
THEODORE JACQUES
Affiliation:
Departments of Psychology and Neuroscience Program, Colgate University, Hamilton, New York
AARON P. JOHNSON
Affiliation:
Department of Psychology, Concordia University, Montréal, Quebec, Canada
DAVE ELLEMBERG
Affiliation:
Centre de recherche en neuropsychologie et cognition (CERNEC), Université de Montréal, Quebec, Canada
*
†Address correspondence and reprint requests to: Bruce C. Hansen, Department of Psychology, Neuroscience Program, Colgate University, 107B Olin Hall, Hamilton, NY 13346. E-mail: [email protected]
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Abstract

The contrast response function of early visual evoked potentials elicited by sinusoidal gratings is known to exhibit characteristic potentials closely associated with the processes of parvocellular and magnocellular pathways. Specifically, the N1 component has been linked with parvocellular processes, while the P1 component has been linked with magnocellular processes. However, little is known regarding the response properties of the N1 and P1 components during the processing and encoding of complex (i.e., broadband) stimuli such as natural scenes. Here, we examine how established physical characteristics of natural scene imagery modulate the N1 and P1 components in humans by providing a systematic investigation of component modulation as visual stimuli are gradually built up from simple sinusoidal gratings to highly complex natural scene imagery. The results suggest that the relative dominance in signal output of the N1 and P1 components is dependent on spatial frequency (SF) luminance contrast for simple stimuli up to natural scene imagery possessing few edges. However, such a dependency shifts to a dominant N1 signal for natural scenes possessing abundant edge content and operates independently of SF luminance contrast.

Keywords

Natural scenesImage complexityScene statisticsSparsenessAmplitude spectrumvisual evoked potentials
Type
Research Articles
Information
Visual Neuroscience , Volume 28 , Issue 3 , May 2011 , pp. 221 - 237
Copyright
Copyright © Cambridge University Press 2011

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