A roadmap to a columnar visual cortical prosthetic

Visual blindness affects many millions globally and severely impacts quality of life. One approach to overcome visual blindness is the direct electrical microstimulation of brain circuits normally engaged in visual function. Attempts to do so with traditional brain-machine interfaces (BMI) in monkeys and humans have evoked percepts (phosphenes) described as crude featureless spots of light. Here, we propose to qualitatively enhance these percepts by recruiting submillimeter units of cortical representation (cortical columns) which encode rich visual features such as color, motion, shape, and faces. A three step roadmap is proposed, comprising: (1) the mapping of column-based networks (columnar connectomes), (2) connectome-guided studies of circuitry and perception, and (3) column-targeted design of optical BMIs. We predict this approach will increase the specificity and sophistication needed for realistic, vibrant visual perception.