Thought-controlled robot unveiled

A partially paralysed person has controlled a robot using brain signals alone for the first time.

Scientists at Switzerland's Federal Institute of Technology in Lausanne said the experiment takes them a step closer to enabling immobile patients to easily interact with their surroundings through a robot 'avatar.'

The demonstration involved a patient at a hospital in the town of Sion who imagined lifting his fingers to direct a robot at the university 60 miles away.

Similar experiments have taken place in the United States and Germany but they either involved able-bodied patients or invasive brain implants, while the Swiss team used only a simple head cap to record the brain signals.

Mark-Andre Duc's thoughts - or rather, the electrical signals emitted by his brain when he imagined lifting his paralysed fingers - were decoded almost instantly by a laptop at the hospital. The resulting instructions - left or right - were then transmitted to a foot-tall robot scooting around the Lausanne lab.

Mr Duc lost control of his legs and fingers in a fall and is now considered partially quadriplegic. He said controlling the robot was not hard on a good day. "But when I'm in pain it becomes more difficult," he said.

Background noise caused by pain or even a wandering mind has emerged as a major challenge in the research of so-called brain-computer interfaces since they first began to be tested on humans more than a decade ago, said Jose Millan, who led the Swiss team.

While the human brain is perfectly capable of performing several tasks at once, a paralysed person would have to focus the entire time they are directing the device.

"Sooner or later your attention will drop and this will degrade the signal," he said. To get around this problem, his team decided to program the computer that decodes the signal so that it works in a similar way to the brain's subconscious. Once a command such as 'walk forward' has been sent, the computer will execute it until it receives a command to stop or the robot encounters an obstacle.

The robot itself is an advance on a previous project that let patients control an electric wheelchair. By using a robot complete with a camera and screen, users can extend their virtual presence to places that are arduous to reach with a wheelchair, such as an art gallery or a wedding abroad.