Until now, most visual prostheses work by stimulating the optic nerve or the brain’s cortex.
But there’s a new sheriff in town called the Optogenetic Brain System. It’s being cooked up by researchers at SUNY Downstate Health Sciences University in Brooklyn, New York, who are developing a new visual prosthetic system. It pulls together genetically engineered neural cells, a brain implant, and a camera and a video projector that is helping blind people see again.
The technology hinges on turning neurons within the visual pathway into photoreceptors, which can then be activated and constantly monitored to calibrate system performance. Since these photoreceptors will be designed to bioluminescence when firing, a feedback loop will allow the system to make sure that the proper signals are transmitted to and received by the neurons.
To guarantee that the user will see what is in the center of the visual field, eye trackers will help select which images to transmit to the brain.
The Optogenetic Brain System is part of the Brain Research through Advancing Innovative Neurotechnologies (BRAIN) Initiative organized by the National Institutes of Health (NIH).
What is Optogenetics?
The brain is a large network of interconnected neurons where each cell functions as a nonlinear processing element. Unraveling the mysteries of information processing in the complex networks of the brain requires versatile neurostimulation and imaging techniques. Optogenetics is a new stimulation method that allows the activity of neurons to be modulated by light. For this purpose, the cell-types of interest are genetically targeted to produce light-sensitive proteins. Once these proteins are expressed, neural activity can be controlled by exposing the cells to light.
Optogenetics provides a unique combination of features, including multimodal control over neural function and genetic targeting of specific cell-types. Together, they form a powerful experimental approach for the study of the circuitry of psychiatric and neurological disorders.
The advent of optogenetics was followed by extensive research aimed to produce new lines of light-sensitive proteins and to develop new technologies that control light distribution inside the brain tissue, or to combine optogenetics with other electrophysiology, electrocorticography, nonlinear microscopy, and functional magnetic resonance imaging.
Read more about advances in optogenetics and related technologies and the future of the field at the NIH.