Adaptation to a "spatial-frequency doubled" stimulus.

P Thompson; B J Murphy

doi:10.1068/p090523

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Adaptation to a "spatial-frequency doubled" stimulus.

P Thompson·B J Murphy

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Abstract

The perceived spatial frequency of low-frequency sinusoidal gratings is elevated when the gratings are temporally modulated sufficiently rapidly. Although this phenomenon is usually called "spatial-frequency doubling", the magnitude of this spatial-frequency elevation depends on the spatial and temporal parameters of the grating and may be less than or greater than doubling. Adaptation to such a pattern produces contrast-threshold elevation whose spatial-frequency tuning is centered upon the grating's real rather than perceived spatial frequency. These results suggest that the spatial-frequency elevation occurs later in the visual system than adaptation or that these two processes are independent of one another, at least under the conditions of these experiments.

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Adaptation, Ocular Differential Threshold Female Humans Male Photic Stimulation Space Perception Time Factors Visual Perception Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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P Thompson, B J Murphy. 1980. Adaptation to a "spatial-frequency doubled" stimulus.. https://doi.org/10.1068/p090523

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