Color filling-in under steady fixation: behavioral demonstration in monkeys and humans.

Journal Article (Journal Article)

Color filling-in is a phenomenon in which the color of an object appears to be filled-in by the color of the surrounding field. We have studied the question of whether monkeys perceive color filling-in with near-foveal stimuli under steady fixation. Two monkeys were trained to fixate steadily and to attend to a disk, surrounded by an annulus of the complementary color, in parafoveal vision. Using displays in which the color of the disk was gradually changed to that of the annulus, we trained the animals to signal when they perceived a uniform color field. During the experiment, we introduced a small percentage of trials in which the disk color remained constant, and looked for 'filling-in' responses in these trials. Three human subjects were also tested for comparison. All subjects produced 'filling-in' responses with frequencies that were significantly higher for static disks with blurred borders than for moving disks or disks with sharp borders. This indicates that the monkeys' responses reflected perceptual filling-in, rather than random behavior. The time course of filling-in was similar in monkeys and humans. For the blurred static disks, responses occurred first after 3-4 s of fixation, reaching a probability of 0.2-0.8 by the end of 6 s, depending on the subject.

Full Text

Duke Authors

Cited Authors

  • Friedman, HS; Zhou, H; von der Heydt, R

Published Date

  • 1999

Published In

Volume / Issue

  • 28 / 11

Start / End Page

  • 1383 - 1395

PubMed ID

  • 10755147

International Standard Serial Number (ISSN)

  • 0301-0066

Digital Object Identifier (DOI)

  • 10.1068/p2831


  • eng

Conference Location

  • United States