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PubMed · 1771777

Spatial-interval discrimination in two-dimensions.

B C Jiang·D M Levi
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Abstract

This study is concerned with the precision of spatial-interval discrimination when the stimulus is varied in two-dimensions rather than one-dimension. For the two-dimensional task, observers were required to judge the centrality of a dot within a circle. Similar measurements were made in a one-dimensional task, i.e. the test dot was displaced only along one meridian, and the results were compared. This study shows that thresholds for the two-dimensional task are approx. square root of 2 times the threshold of the one-dimensional task when the observer's task is to simply detect an offset in both one- and two-dimensional conditions. However, thresholds are about a factor of two higher for the two-dimensional task if the observer is required to label the direction of offset.

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Discrimination, PsychologicalHumansPsychophysicsSensory ThresholdsSpace PerceptionVisual AcuityJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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BibTeXRIS

B C Jiang, D M Levi. 1991. Spatial-interval discrimination in two-dimensions.. https://doi.org/10.1016/0042-6989(91)90188-b

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