At 70 years Hawking's condition is worsening so communication "talking" via computer more difficult. Now he's practicing with iBrain to use brainwaves, but this technology has a long way to go.
Researchers will unveil their latest results at a conference in Cambridge next month, and may demonstrate the technology on Hawking.
It is hoped that as the technology becomes more advanced it could recognise more sophisticated brain activity and turn it into words.
Scientists hope that it may soon be able to "read a person's mind," playing a major role in a medical breakthrough.