Sensory Substitution Devices as Advanced Sensory Tools

There has been considerable effort devoted towards understanding sensory substitution devices in terms of their relationship to canonical sensory modalities. The approach taken in this essay is rather different, although complementary, in that we seek to define a broad conceptual space of ‘sensory tools’ in which sensory substitution devices can be situated. Such devices range from telescopes, to cochlear implants, to attempts to create a magnetic sense. One feature of these devices is that they operate at the level of ‘raw’ sensory information. As such, systems such as Braille which operate at a symbolic/conceptual level do not count as a sensory tool (or a sensory substitution device) and nor would a device such as CCTV which, although capturing raw sensory information, would not meet a conventional definition of a tool. With this approach, we hope to avoid the circularity inherent in previous attempts at defining sensory substitution and provide a better starting point to explore the effects of sensory tools, more generally, on the functioning of the nervous system.