Sensory Restoration and Substitution

One way of coping with blindness and deafness has been some form of sensory substitution—allowing one or more remaining senses to take over for the nonfunctioning sense. Because the senses of vision, hearing, and touch all convey information about the physical and social environments, they can substitute for each other to varying extents. However, because unaided sensory substitution is only partially effective, humans have long improvised with artifices to facilitate sensory substitution (e.g., Braille and the long white cane for blindness, sign language for deafness, and the Tadoma method of speech reception used by deaf and blind people, in which the listener places the hand over the mouth and jaw of the speaker in order to sense articulatory speech information). In recent decades, the advent of electronics and computers has resulted in assistive technology that greatly enhances sensory substitution and, in some cases, allows for the restoration of a nonfunctioning sensory apparatus. This entry discusses the correction and restoration of the senses, as well as sensory substitutions by use of abstract meaning, amodal spatial representations, synesthesia, rote learning, and brain plasticity.