Optical images of visible and invisible percepts in the primary visual cortex of primates.

Journal Article (Journal Article)

We optically imaged a visual masking illusion in primary visual cortex (area V-1) of rhesus monkeys to ask whether activity in the early visual system more closely reflects the physical stimulus or the generated percept. Visual illusions can be a powerful way to address this question because they have the benefit of dissociating the stimulus from perception. We used an illusion in which a flickering target (a bar oriented in visual space) is rendered invisible by two counter-phase flickering bars, called masks, which flank and abut the target. The target and masks, when shown separately, each generated correlated activity on the surface of the cortex. During the illusory condition, however, optical signals generated in the cortex by the target disappeared although the image of the masks persisted. The optical image thus was correlated with perception but not with the physical stimulus.

Full Text

Duke Authors

Cited Authors

  • Macknik, SL; Haglund, MM

Published Date

  • December 21, 1999

Published In

Volume / Issue

  • 96 / 26

Start / End Page

  • 15208 - 15210

PubMed ID

  • 10611363

Pubmed Central ID

  • PMC24798

International Standard Serial Number (ISSN)

  • 0027-8424

Digital Object Identifier (DOI)

  • 10.1073/pnas.96.26.15208


  • eng

Conference Location

  • United States