Perceptual restoration fails to recover unconscious processing for smooth eye movements after occipital stroke
Abstract
The visual pathways that guide actions do not necessarily mediate conscious perception. Patients with primary visual cortex (V1) damage lose conscious perception but often retain unconscious abilities (e.g. blindsight). Here, we asked if saccade accuracy and post-saccadic following responses (PFRs) that automatically track target motion upon saccade landing are retained when conscious perception is lost. We contrasted these behaviors in the blind and intact fields of 11 chronic V1-stroke patients, and in 8 visually-intact controls. Saccade accuracy was relatively normal in all cases. Stroke patients also had normal PFR in their intact fields, but no PFR in their blind fields. Thus, V1 damage did not spare the unconscious visual processing necessary for automatic, post-saccadic smooth eye movements. Importantly, visual training that recovered motion perception in the blind field did not restore the PFR, suggesting a clear dissociation between pathways mediating perceptual restoration and automatic actions in the V1-damaged visual system.
Data availability
Data for all figures has been shared on the Dryad.https://doi.org/10.6078/D1W69T
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Data from: Perceptual restoration fails to recover unconscious processing for smooth eye movements after occipital strokesDryad Digital Repository, doi.org/10.6078/dryad.D1W69T.
Article and author information
Author details
Funding
National Eye Institute (EY027314)
- Krystel R Huxlin
National Eye Institute (EY021209)
- Krystel R Huxlin
National Eye Institute (EY030998)
- Jude F Mitchell
Research to Prevent Blindness
- Krystel R Huxlin
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: Human subjects: All experimental protocols were conducted according to the guidelines of the Declaration of Helsinki and approved by The Research Subjects Review Board at the University of Rochester Medical Center (#00021951). Informed written consent was obtained from all participants prior to participation. Participants were compensated $15/hour.
Copyright
© 2022, Kwon et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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