A model for intracortical visual prosthesis research

In the field of visual prosthesis research, it has generally been held that animal models are limited to testing the safety of implantable hardware due to the inability of the animal to provide a linguistic report of perceptions. In contrast. vision scientists make extensive use of trained animal models to investigate the links between visual stimuli, neural activities. and perception. We describe an animal model for cortical visual prosthesis research in which novel animal psychophysical testing has been employed to compensate for the lack of a linguistic report. One hundred and fifty-two intracortical microelectrodes were chronically implanted in area V1 of a male macaque. Receptive field mapping was combined with eye-tracking to develop a reward-based training procedure. The animal was trained to use electrically induced point-flash percepts, called phosphenes, in performing a memory saccade task. It is our long-term goal to use this animal model to investigate stimulation strategies in developing a multichannel sensory cortical interface.