Blindsight in normal observers
- Creators
- Kolb, F. Christopher
- Braun, Jochen
Abstract
Some patients with lesions in visual cortex lack conscious visual experience but, when tested, exhibit a significant ability, termed 'blindsight', to discriminate visual stimuli. Here we report two different visual displays that induce blindsight in normal observers. Using an objective measure, we show that conscious experience remains defective at presentation times much longer (1 s) than the onset of visual sensitivity (˜60 ms). To obtain this effect, we generate a contrast between visual textures and then conceal the contrast by superimposing 'complementary' textures. Complementarity can involve either opposite motion or binocular rivalry and orthogonal orientation. In both cases, observers locate the texture contrast reliably but do not, by either subjective or objective measures, consciously experience it. Taken together with present knowledge of the visual cortical site(s) at which opposite motion and rivalrous orientation interact, this observation bears upon the functional anatomy of conscious visual experience.
Additional Information
© 1995 Nature Publishing Group. Supported by the Sloan Foundation and the NSF, Division of Integrative Biology and Neuroscience and Center for Neuromorphic Systems Engineering, as part of the Engineering Research Center Program. We thank P. Perona for facilities, C. Koch for discussion, and A. Dobbins for access to unpublished work on a related topic.Additional details
- Eprint ID
- 40451
- DOI
- 10.1038/377336a0
- Resolver ID
- CaltechAUTHORS:20130816-103209120
- Sloan Foundation
- NSF
- Division of Integrative Biology and Neuroscience
- Center for Neuromorphic Systems Engineering
- Engineering Research Center at Caltech
- Created
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2008-01-26Created from EPrint's datestamp field
- Updated
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2021-11-09Created from EPrint's last_modified field
- Caltech groups
- Koch Laboratory (KLAB)