Other than florists and allergy sufferers, most people don’t do much sniffing. But scientists in Israel see the ability as a way to assist severely paralyzed people. In the August 10 issue of the Proceedings of the National Academy of Sciences USA, Noam Sobel and his team at the Weizmann Institute of Science in Rehovot described the first ever sniff-enabled device: a thin plastic tube with two short prongs that are inserted into the nostrils. The gadget measures nasal pressure and converts it into electrical signals that can be read by a computer. The researchers found that, by sniffing, people could quickly and accurately raise or lower their nasal pressure enough to trigger a command, similar to pressing a button.
When playing a computer game using the device, healthy users performed as well as they did with a handheld mouse or joystick without fatiguing, as happens to hands during sustained play. A quadriplegic person learned after 15 minutes of practice to use patterns of sniffing to drive an electric wheelchair, and two out of three people with locked-in syndrome marked by complete paralysis—were able to control their sniffing enough to use the device to select letters from a virtual keyboard. One of the locked-in people was able to communicate for the first time, and the other reported that the device was easier to use than the more established ones that monitor eye movement or blinks. Because the invention is cheap to make and not easily dislodged by motion, it could become widely available for people with disabilities.