What limits simultaneous discrimination accuracy?

J P Thomas; S Magnussen; M W Greenlee

doi:10.1016/s0042-6989(00)00169-3

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What limits simultaneous discrimination accuracy?

J P Thomas·S Magnussen·M W Greenlee

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Abstract

Discrimination accuracy decreases when viewers simultaneously monitor two perceptually distinct stimulus components for changes in a common property, e.g. contrast [Magnussen & Greenlee (1997). Journal of Experimental Psychology: Human Perception and Performance, 23, 1603-1616; Olzak & Wickens (1997). Perception, 26, 1101-1120]. We ask whether the limitation is in monitoring two components or in making dual decisions about a single property. Using the same uncertainty paradigm as Magnussen and Greenlee, we find no evidence of a processing limitation when viewers simultaneously monitor one component (1.25 c/d) for a possible change in contrast and a second component (5 c/d) for a possible change in spatial frequency, regardless of whether the components are spatially separated or superimposed. The limitation is in making dual decisions about a single property.

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Attention Contrast Sensitivity Decision Making Humans Space Perception Visual Perception Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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J P Thomas, S Magnussen, M W Greenlee. 2000. What limits simultaneous discrimination accuracy?. https://doi.org/10.1016/s0042-6989(00)00169-3

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