I found the following story on the NPR 
http://www.npr.org/blogs/health/2010/07/26/128776406/communication-technology-for-disable-is-nothing-to-sniff-at?sc=17&f=1128

Communication Technology For Disabled Is Nothing To Sniff At
by Meagen Voss

- July 26, 2010

There’s a new way for severely disabled people to communicate with the outside world — sniffing. That’s right. Sniffing.

Israeli scientists have created a nose-powered device that severely paralyzed can use to control a computer. A small tube carries the breath of a person to a tiny sensor that detects changes in pressure. A computer translates the puffs into letters, allowing the  person to type.

"I have a locked-in patient who sends me e-mails," says Noam Sobel, a neuroscientist at Weizmann Institute in Israel who’s developing the approach.

People with locked-in syndrome are almost completely paralyzed, but mentally normal. Three of the 15 disabled people included in the study by Sobel and his colleagues were locked-in. Typically, those patients rely on caretakers to interpret eye blinks for communication. That's a slow and laborious way to have a conversation.

Sobel says the sniffing device lets these patients "generate really meaningful self-initiated _expression_." The work is described in the latest edition of the Proceedings of the National Academy of Sciences.

An advantage of the sniff device, says Sobel, is it cannot only detect when a person starts or stops sniffing, but also sense how long the sniff lasts and how strong it is. All that information, Sobel says, makes it easier to create programs for performing complex tasks, like surfing the Web.

The device can also be used on people who have a breathing tube. As long as people can move their soft palate, the muscle that lets us switch between breathing with our nose or our mouth, the sniff device can pick up the pressure changes in the nose.

Still, the device isn't for everyone. "I have several patients who refuse to use technology because they want that human to human interaction," says Lisa Bruning, a speech therapist who works with amyotrophic lateral sclerosis patients.

ALS, or Lou Gehrig’s disease, saps people of control over their muscles. Virtually everyone who suffers from ALS will eventually become locked-in.  But because the disease starts in different parts of the body in different people, some may lose control over their speech muscles first, including the soft palate. That wouldn’t be able to use the new device.

Communicating through a caretaker doesn’t prevent locked-in patients from living meaningful lives. One man dictated a book using eye blinks. But, says neuroscientist John Donghue, "Those methods are painfully slow."

Donoghue is a principal investigator for the BrainGate project. He and his team have created implants that read a disabled person’s brainwaves and give them the ability to control a computer, a prosthetic limb, even a wheelchair. But these implants are still early in development.

In the meantime, he agrees that the sniff device could help. He says, "Anything that adds to the armamentarium of things that we have to help these people communicate is a good thing."

What Sobel likes about his sniff device is that it's simple, low-tech and cheap to produce. He said the prototypes cost around $300. Plus, the sniff device can be used to drive a wheelchair too. Two breaths in move you forward. Two breaths out, move you backward.

Whether the sniff device will catch on depends on a disabled person’s preferences. Most likely the device will be used in combination with other systems. After all, there’s one thing that will shut down the sniff device real fast — a cold. [Copyright 2010 National Public Radio]

To learn more about the NPR iPhone app, go to http://iphone.npr.org/recommendnprnews