 Tactile sensory systems have proven capable of carrying information to the brain that is usually acquired visually. Braille and the long cane have provided such information to blind persons for decades, and in the 1960s it was clearly demonstrated that tactile inputs could provide access to written print1 and visual images2. The main limitation to the development of practical vision substitution has been the inadequacy of brain-machine interfaces. Thirty-five years ago Paul Bach-y-Rita, MD wrote That a successful sensory substitution system is not presently in use may not be due to limited functional capabilities of the brain; it may be due to the fact that an artificial receptor system has not yet been constructed to challenge the adaptive capacities of the human brain3. 