Similarity Grouping of Curves

Abstract

The grouping of curves was investigated by measuring the time taken to count the disparate figures in a display and by ratings When line curvature was the only differentiating property, the grouping of the disparate figures was poor. Grouping of disparate figures corresponded to the judged similarities of the background and disparate figures when the similarity judgments varied with stimulus differences measured in terms of discriminability but not when similarity judgments varied with stimulus differences measured in terms of the sameness of the transformation which applied to the background figures produced the disparate figures. The results are interpreted as supporting the hypothesis that similarity grouping is based on the response of the visual system to extra-foveal stimulus differences in a patterned visual field when attention is not concentrated or focused.