Via Instapundit and Daily Mail:
A headset detects the tongue’s position when the user flicks that magnetic stud. Touch a spot on the right bottom tooth to go right, for example.
The headset wirelessly beams that information to a smartphone the user carries. An app then sends the command to move the wheelchair or the computer cursor.
Click the link to see more: Tongue Drive System is a piercing that controls wheelchair | Mail Online