A novel interface for cortical columnar neuromodulation with multipoint infrared neural stimulation.

Cutting edge advances in electrical visual cortical prosthetics have evoked perception of shapes, motion, and letters in the blind. Here, we present an alternative optical approach using pulsed infrared neural stimulation. To interface with dense arrays of cortical columns with submillimeter spatial precision, both linear array and 100-fiber bundle array optical fiber interfaces were devised. We deliver infrared stimulation through these arrays in anesthetized cat visual cortex and monitor effects by optical imaging in contralateral visual cortex. Infrared neural stimulation modulation of response to ongoing visual oriented gratings produce enhanced responses in orientation-matched domains and suppressed responses in non-matched domains, consistent with a known higher order integration mediated by callosal inputs. Controls include dynamically applied speeds, directions and patterns of multipoint stimulation. This provides groundwork for a distinct type of prosthetic targeted to maps of visual cortical columns. Visual perception is achieved by a chain of specific neural activations in the brain. Here, the authors show that infrared neural stimulation of selected early nodes in the chain leads to predictable shape response in higher areas, providing groundwork for targeted approach to vision restoration. [ABSTRACT FROM AUTHOR]