Toward a Bidirectional Communication Between Retinal Cells and a Prosthetic Device - A Proof of Concept

Area of Science:

• Neuroscience
• Biomedical Engineering
• Ophthalmology

Background:

• Current visual prostheses offer electrical stimulation (ES) for vision restoration but lack feedback mechanisms.
• Retinal remodeling necessitates adaptive stimulation strategies for improved therapeutic efficiency.
• There is a need for devices that provide real-time retinal activity information alongside ES.

Purpose of the Study:

• To propose and validate a bidirectional communication strategy for retinal prostheses.
• To develop and test custom penetrating microelectrode arrays (MEAs) for simultaneous stimulation and recording.
• To enable a feedback loop system for adaptive ES in visual prostheses.

Main Methods:

• Utilized custom-designed penetrating MEAs with silicon shanks and iridium oxide electrodes.
• Recorded *in vitro* retinal activity from wildtype and *rd10* mice.
• Examined responses to potassium and light stimulation, and performed voltage-controlled ES.

Main Results:

• Successfully recorded retinal ganglion cell (RGC) spiking activity at various retinal depths.
• Captured physiological and pathological retinal activity, including responses to stimuli.
• Achieved simultaneous ES of the inner retina and RGC recording.

Conclusions:

• Penetrating MEAs allow access to diverse retinal layers for simultaneous RGC recording.
• The developed bidirectional MEA (BiMEA) enables simultaneous electrical stimulation and RGC recording.
• BiMEA technology facilitates a feedback system for optimizing ES in retinal prostheses.