Contributed Talks I: Recruiting native visual representations in visual cortex for electrode array based vision...

Area of Science:

• Neuroscience
• Biomedical Engineering
• Visual Prosthetics

Background:

• Recruiting native functional representations in the visual cortex via external stimulation is key for advancing visual prosthetics.
• Directly measuring neural responses to visual input is impossible in blind humans, necessitating alternative methods to assess neuronal function.

Purpose of the Study:

• To develop and validate a method for inferring orientation preference maps from spontaneous neural activity.
• To apply this method to recordings from blind human volunteers with cortical visual prostheses to understand perception.

Main Methods:

• Developed a method to infer orientation preference maps from spontaneous activity recorded using a Utah array in the primary visual cortex.
• Validated the method using computational models of the primary visual cortex and electrophysiological recordings from macaque V1.
• Applied the method to recordings from blind humans implanted with a cortical visual prosthesis.

Main Results:

• The method successfully inferred orientation preference maps from spontaneous activity.
• In blind human volunteers, both spatial and functional properties of stimulated electrodes significantly affected perceived visual input.
• Increased spatial and functional separation between stimulated electrode sets enhanced stimulus discrimination.

Conclusions:

• Spontaneous neural activity contains information about functional representations in the visual cortex.
• The inferred orientation maps are functionally relevant for electrically evoked perception in humans.
• This approach demonstrates the potential for guiding visual prosthesis stimulation based on decoded neural representations.