Citation

Toscani M, Valsecchi M. Iperception 2019; 10(6): e2041669519884335.

Affiliation

Department of Psychology, Giessen University, ‎Hesse, Germany.

Copyright

(Copyright © 2019, SAGE Publishing)

DOI

10.1177/2041669519884335

PMID

31803462

PMCID

PMC6876175

Abstract

The brighter portions of a shaded complex object are in principle more informative about its lightness and are preferentially fixated during lightness judgments. In this study, we investigate whether preventing this strategy also has measurable detrimental effects on performance. Observers were presented with a reference and a comparison three-dimensional rendered object and had to choose which one was "painted with a lighter gray." The comparison was rendered with different diffuse reflectance values. We compared precision between three different conditions: full image, 20% of the lightest pixels removed, or 20% of the darkest pixels removed. Removing the bright pixels maximally impaired performance. The results confirm that the strategy of relying on the brightest areas of a complex object in order to estimate lightness is functionally optimal, yielding more precise representations.

© The Author(s) 2019.

Language: en

Keywords

lightness/brightness; natural image statistics; object recognition; perception; surfaces/materials