Visual percepts evoked with an Intracortical 96-channel microelectrode array inserted in human occipital cortex

Publication/Creation Date
October 19 2021
Media Type
Journal Article
Persuasive Intent
Discursive Type

BACKGROUND: A long-held dream of scientists is to transfer information directly to the visual cortex of blind individuals, thereby restoring a rudimentary form of sight. However, no clinically available cortical visual prosthesis yet exists.

METHODS: We implanted an intracortical microelectrode array consisting of 96 electrodes in the visual cortex of a 57-year-old person with complete blindness for a six month period. We measured thresholds and the characteristics of the visual percepts elicited by intracortical microstimulation.

RESULTS: Implantation and subsequent  explantation of intracortical microelectrodes were carried out without complications. The mean stimulation threshold for single electrodes was 66.8 ± 36.5 μA. We consistently obtained high-quality recordings from visually deprived neurons and the stimulation parameters remained stable over time. Simultaneous stimulation via multiple electrodes were associated with a significant reduction in thresholds (p<0.001, ANOVA test) and evoked discriminable phosphene percepts, allowing the blind participant to identify some letters and recognize object boundaries.

CONCLUSIONS: Our results demonstrate the safety and efficacy of chronic intracortical microstimulation via a large number of electrodes in human visual cortex, showing its high potential for restoring functional vision in the blind.
HCI Platform
Relation to Body
Related Body Part
Brain, Eye

Date archived
October 25 2021
Last edited
October 25 2021
How to cite this entry
Eduardo Fernández, Richard A. Normann, Arantxa Alfaro, Cristina Soto-Sánchez, Pablo Gonzalez-Lopez, Antonio M. Lozano Ortega, Sebastian Peña, Maria Dolores Grima, Alfonso Rodil, Berna Gómez, Xing Chen, Pieter R. Roelfsema, John D. Rolston, Tyler S. Davis. (October 19 2021). "Visual percepts evoked with an Intracortical 96-channel microelectrode array inserted in human occipital cortex ". Journal of Clinical Investigation. American Society for Clinical Investigation. Fabric of Digital Life.