The device in the photo is a dental retainer similar to the ones a lot of us wore in our teens, but with circuitry embedded within and contacts at the six points shown in the diagram. A tongue stud makes contact with one of them to issue a steering command to the wheelchair. It can also synch with an iPod Touch or an iPhone. This invention opens up much greater ranges of mobility and communication for people with severe spinal injuries.
For more see wired.
Be seeing you.