Rod temporal channels.

R F Hess; S J Waugh; K Nordby

doi:10.1016/0042-6989(96)89254-6

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PubMed · 8855005

Rod temporal channels.

R F Hess·S J Waugh·K Nordby

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Abstract

Mechanisms underlying rod temporal contrast sensitivity have been considered in terms of a fast retinal signal predominating at mesopic levels and a slower retinal signal predominating at scotopic levels. Here we use a small signal masking method, which has previously been used to delineate the cone-mediated cortical temporal channels, to investigate their rod-mediated cortical counterparts. The results suggest that there are three different rod-mediated cortical temporal channels, one which is lowpass and two which are bandpass. These mechanisms co-exist at all light levels and their relative sensitivity depend on the stimulus spatio-temporal frequency.

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Color Vision Defects Contrast Sensitivity Humans Male Perceptual Masking Psychophysics Retinal Rod Photoreceptor Cells Sensory Thresholds Spectrophotometry Time Factors Visual Cortex Visual Pathways Journal Article Research Support, Non-U.S. Gov't

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R F Hess, S J Waugh, K Nordby. 1996. Rod temporal channels.. https://doi.org/10.1016/0042-6989(96)89254-6

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