TECHNOLOGY FOR CHANGE

Sniffing Device Enables the Paralyzed to Communicate

Rebecca Kutzer-Rice | Date: 08-04-10 | Comments

Although it looks like an oxygen-delivery tube, this device may be the key to communication for patients who lack mobility.

Recently, I wrote about a pair of bionic legs that enables paraplegics to walk and even climb stairs. As exciting as this technology is, it will only be useful for those paralyzed from the waist down. For people with more substantial injuries�like quadriplegics and those with �locked-in� syndrome�more immediate needs must be addressed, such as communication. A team of Israeli researchers is developing a device to allow people lacking mobility to communicate and control their wheelchairs�simply by sniffing.

Although it looks like an oxygen-delivery tube, this device may be the key to communication for patients who lack mobility.

The researchers� results are upcoming in the Proceedings of the National Academy of Sciences. In the paper, they describe the need for technology to improve the quality of life for paralyzed patients: �Paradoxically, improvements in emergency medicine have rendered injuries previously fatal into injuries that are now survived yet accompanied by life-long severe disability ranging from quadriplegia to �locked-in syndrome.�� Usually resulting from trauma, a stroke, or amyotrophic lateral sclerosis (ALS), locked-in syndrome occurs when a patient has unharmed cognition but a completely paralyzed body.

In best-case scenarios, locked-in patients are only able to communicate using blinks of the eye. The syndrome was made famous by Jean-Dominique Bauby, a French journalist who became locked-in following a stroke at the age of 43. While paralyzed, Bauby tediously dictated his now-celebrated memoir, The Diving Bell and the Butterfly, by blinking his left eye. He died several days after it was published.

The new device could make communication easier for patients in Bauby�s situation. Called a �sniff controller,� the apparatus converts nasal pressure into electrical signals, thereby allowing locked-in patients to write messages and control wheelchairs. Worn externally, the controller is similar in appearance to the rubber oxygen-delivery tubes that many patients wear.

In small group studies, the device has shown impressive promise. When used with a word-completion program, the controller allowed several locked-in patients to communicate successfully. The team also created an interface to allow patients to control electric wheelchairs with the device. Sniffing in twice allowed the patient to move forward, while sniffing out twice allowed them to move backward. After only 15 minutes, the test patients had learned to easily control the devices.

Unfortunately, the device requires substantial control over the soft palate, part of the nasal cavity, to manage the strength of sniffs. While control of this body part usually remains intact in paralyzed patients, not all people can move it to begin with. In the study, about a quarter of the healthy patients tested could not sufficiently control their soft palates to control the device. Still, many paralyzed patients may be able to use the controller for communication and movement�thereby enhancing their freedom and improving their quality of life.