Eye movements and the perceived location of phosphenes generated by intracranial primary visual cortex stimulation in the blind.
Blind
Eye movements
Neurostimulation
Visual cortex
Visual prosthesis
Journal
Brain stimulation
ISSN: 1876-4754
Titre abrégé: Brain Stimul
Pays: United States
ID NLM: 101465726
Informations de publication
Date de publication:
Historique:
received:
20
11
2020
revised:
23
04
2021
accepted:
26
04
2021
pubmed:
16
5
2021
medline:
25
11
2021
entrez:
15
5
2021
Statut:
ppublish
Résumé
Restoring sight for the blind using electrical stimulation of the visual pathways is feasible but demands an understanding of the spatial mapping of the visual world at the site of targeted stimulation, whether in the retina, thalamus, or cortex. While a visual cortex stimulator can bypass the eye and create visual percepts, there is an inherent dissociation between this stimulation and eye movements. It is unknown whether and how robustly the brain maintains the oculomotor circuitry in patients with bare- or no-light perception. To critically and quantitatively evaluate the effect of eye movements have on phosphene locations elicited by cortical stimulation that bypasses the eyes in order to restore sight in blind subjects. The NeuroPace Responsive Neurostimulator (RNS) and the Orion visual cortical prosthesis devices were used to electrically stimulate the visual cortex of blind subjects with bare or no light perception. Eye positions were recorded synchronized with stimulation and the location of the percepts were measured using a handheld marker. The locations of cortical stimulation-evoked percepts are shifted based on the eye position at the time of stimulation. Measured responses can be remapped based on measured eye positions to determine the retinotopic locations associated with the implanted electrodes, with remapped responses having variance limited by pointing error. Eye movements dominate the perceived location of cortical stimulation-evoked phosphenes, even after years of blindness. By accounting for eye positions, we can mimic retinal mapping as in natural sight.
Sections du résumé
BACKGROUND
Restoring sight for the blind using electrical stimulation of the visual pathways is feasible but demands an understanding of the spatial mapping of the visual world at the site of targeted stimulation, whether in the retina, thalamus, or cortex. While a visual cortex stimulator can bypass the eye and create visual percepts, there is an inherent dissociation between this stimulation and eye movements. It is unknown whether and how robustly the brain maintains the oculomotor circuitry in patients with bare- or no-light perception.
OBJECTIVE
To critically and quantitatively evaluate the effect of eye movements have on phosphene locations elicited by cortical stimulation that bypasses the eyes in order to restore sight in blind subjects.
METHODS
The NeuroPace Responsive Neurostimulator (RNS) and the Orion visual cortical prosthesis devices were used to electrically stimulate the visual cortex of blind subjects with bare or no light perception. Eye positions were recorded synchronized with stimulation and the location of the percepts were measured using a handheld marker.
RESULTS
The locations of cortical stimulation-evoked percepts are shifted based on the eye position at the time of stimulation. Measured responses can be remapped based on measured eye positions to determine the retinotopic locations associated with the implanted electrodes, with remapped responses having variance limited by pointing error.
CONCLUSIONS
Eye movements dominate the perceived location of cortical stimulation-evoked phosphenes, even after years of blindness. By accounting for eye positions, we can mimic retinal mapping as in natural sight.
Identifiants
pubmed: 33991713
pii: S1935-861X(21)00089-9
doi: 10.1016/j.brs.2021.04.019
pii:
doi:
Types de publication
Journal Article
Research Support, N.I.H., Extramural
Langues
eng
Sous-ensembles de citation
IM
Pagination
851-860Subventions
Organisme : NINDS NIH HHS
ID : UH3 NS103442
Pays : United States
Informations de copyright
Copyright © 2021 The Author(s). Published by Elsevier Inc. All rights reserved.
Déclaration de conflit d'intérêts
Declaration of competing interest AC was a consultant and MPB, UKP, MAS, and AR were employees at Second Sight Medical Products, Inc. (SSMP) during the study. JDD is an employee at SSMP. Part of the study was funded by SSMP.