Creating a neuroprosthesis for active tactile exploration of textures

Significance Sensory neuroprostheses offer the promise of restoring perceptual function to people with impaired sensation. Here, we developed a paradigm using intracortical microstimulation (ICMS) for encoding the sensation of fingertip motion against texture. Monkeys learned to interpret time-varying ICMS patterns, evoked by the interplay of their voluntary movements and specific object textures, and discriminated texture coarseness relying solely on these pulse trains. As such, variations in exploration strategy directly affected the timing of individual stimulation pulses. Crucially, this encoding enabled real-time active exploration of textures. We propose that this approach could equip upper-limb neuroprostheses with functional access to texture features acquired during active exploration of natural objects.