People paralysed from the neck down will be able to control keyboards and wheelchairs by sniffing. Even in cases of almost complete paralysis, the ability to coordinate sniffing is often retained because the soft palate – whose movements control sniffing – receives signals from several nerves that are often unaffected by paralytic injuries and disorders.
Scientists at the Weizmann Institute of Science in Rehovot, Israel have thus developed a new sniff controller in which tubes placed up the nose measure changes in nasal air pressure. Quadriplegic volunteers were as able to navigate wheelchairs using combinations of inhalations and exhalations as able-bodied participants. Sniffing was also used to control a cursor and highlight text. A 63-year-old quadriplegic woman who had not written anything for ten years was now using the sniff device to write emails and surf the internet.