Contrast sensitivity of the motion system.

M Edwards; D R Badcock; S Nishida

doi:10.1016/0042-6989(95)00321-5

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Contrast sensitivity of the motion system.

M Edwards·D R Badcock·S Nishida

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Abstract

A number of experiments were conducted to investigate how global-motion performance varies with luminance contrast. When all the dots in the stimulus were the same contrast, performance improved with increasing contrast up to about the 15% level (Experiment 1). Increasing the contrast beyond this level had no additional effect on performance. When the contrast of a subgroup of the dots was varied, differential effects on performance could be obtained for contrasts up to the 80% level (Experiment 2). These results are interpreted as indicating that the performance saturation observed in Experiment 1 was due to the attainment of a performance ceiling at the global-motion level, and not due to contrast-response saturation of the underlying local-motion detectors. The results of earlier studies that have apparently found conflicting results (saturation vs no saturation) are discussed in light of the present results.

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Contrast Sensitivity Humans Light Male Mathematics Models, Neurological Motion Perception Psychophysics Sensory Thresholds Journal Article Research Support, Non-U.S. Gov't

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M Edwards, D R Badcock, S Nishida. 1996. Contrast sensitivity of the motion system.. https://doi.org/10.1016/0042-6989(95)00321-5

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