Hanover, March 11: A computerised typewriter that can read minds was on display at the giant CeBIT high-tech fair, touted as a potential tool to help patients incapacitated by injury or disease to communicate again. Prototypes of the “mental typewriter”, developed by computer scientists from Germany’s renowned Fraunhofer Institute and neurology specialists from Berlin’s Charite Hospital, made their public debut at the event. Two subjects wearing a sort of leather swimming cap covered with a web of wires that were linked to a computer in front of them tested the invention before CeBIT crowds.
While their bodies remained perfectly still, both men imagined movements that were then played out on the screen, one of the developers behind the project, Klaus-Robert Mueller of the Fraunhofer Institute, said. Without either of the men moving a muscle, the cursor on the screen began to float, letters eventually appeared and sentences formed. “They imagined they were putting a ball in their left hand or the right, or that they were moving a door with their feet or shooting a goal,” Mueller explained. Each mental movement triggered an adjustment of the cursor on the screen, and prompted the selection of letters by process of elimination.
The experience is time-consuming at several minutes per sentence. But it works. The swimming cap is equipped with sensors — 64 or 128 according to the model — that like an EEG machine permit the measurement of brain activity. The brain’s electrical signals are transmitted by wire to the computer which can read them and transform them into commands.
The doctors on the team applied their “physiological knowledge of which movement provokes which reaction in which part of the brain,” while the computer scientists converted that information into algorithms, neurology professor Gabriel Curio of the Charite Hospital explained. The developers said they did not believe patients would need much training to learn to use the system. “It’s not the man but the machine that has to learn,” Curio said.
The computer adapts to each person and requires only 15 to 20 minutes to create a personal profile. Then, said Mueller, “the important thing is just to relax and concentrate on a specific movement”.
Curio said the mental typewriter can allow those with various forms of paralysis, “where the brain is intact but trapped in a body that no longer reacts”, to regain their liberty. He said there could also be applications for those using artificial limbs. Just as patients can experience phantom pain after the amputation of a body part, people may be able to imagine “phantom movements” that are carried out by a prosthesis. But do not expect the mental typewriter to hit the market any time soon.