Local computation of lightness on articulated surrounds

Journal Title: i-Perception - Year , Vol 3, Issue 8

Abstract

Lightness of a grey target on a uniform light (or dark) surround changes by articulating the surround (articulation effect). To elucidate the processing of lightness underlying the articulation effect, the present study introduced transparency over a dark surround and investigated its effects on lightness of the target. The transparency was produced by adding a contiguous external field to the dark surround while keeping local stimulus configuration constant. Results showed that the target lightness did not change on the articulated surround when a dark transparent filter was perceived over the target, although it did on the uniform surround. These results suggest that image decomposition into a transparent filter and an underlying surface does not necessarily change lightness of the surface if the surface is articulated. Moreover, the present study revealed that articulating the surround does not always enhance lightness contrast; it can reduce the contrast effect when the target luminance is not the highest within the surround. These findings are consistent with the theoretical view that lightness perception on articulated surfaces is determined locally within a spatially limited region, and they also place a constraint on how the luminance distribution within the limited region is scaled.

Authors and Affiliations

Masataka Sawayama, Eiji Kimura

Keywords

Related Articles

Prevalence effect in haptic search

In visual search tasks, the ratio of target-present to target-absent trials has important effects on miss rates. In this study, we examined whether the target prevalence effect occurs in a haptic search task by using art...

Hearing mouth shapes: Sound symbolism and the reverse McGurk effect

In their recent article, Sweeny, Guzman-Martinez, Ortega, Grabowecky, and Suzuki (2012) demonstrate that heard speech sounds modulate the perceived shape of briefly presented visual stimuli. Ovals, whose aspect ratio (re...

Grouping by closure influences subjective regularity and implicit preference

A reflection between a pair of contours is more rapidly detected than a translation, but this effect is stronger when the contours are closed to form a single object compared to when they are closed to form 2 objects wit...

The utility of defocus blur in binocular depth perception

The question of whether defocus blur is a quantitative cue for depth perception is a topic of renewed interest. A recent study suggests that relative defocus blur can be used in computing depth throughout the visual fiel...

Download PDF file
  • EP ID EP682493
  • DOI  10.1068/i0528
  • Views 109
  • Downloads 0

How To Cite

Masataka Sawayama, Eiji Kimura (). Local computation of lightness on articulated surrounds. i-Perception, 3(8), -. https://europub.co.uk/articles/-A-682493