A scientist waves to Mark-Andre Duc, a partially tetraplegic patient, at Switzerland’s Federal Institute of Technology in Lausanne, Switzerland, Tuesday, April 24, 2012. From the hospital 100 km (62 miles) away, Duc, imagined lifting his fingers to direct a robot. Swiss scientists demonstrated with this test how a partially paralyzed person can control a robot using brain signals alone. AP Photo/Anja Niedringhaus |
Lausanne,
Switzerland (AP)—Swiss scientists have demonstrated how a partially
paralyzed person can control a robot by thought alone, a step they hope
will one day allow immobile people to interact with their surroundings
through so-called avatars.
Similar
experiments have taken place in the United States and Germany, but they
involved either able-bodied patients or invasive brain implants.
On
Tuesday, a team at Switzerland’s Federal Institute of Technology in
Lausanne used only a simple head cap to record the brain signals of
Mark-Andre Duc, who was at a hospital in the southern Swiss town of Sion
100 km (62 miles) away.
Duc’s
thoughts—or rather, the electrical signals emitted by his brain when he
imagined lifting his paralyzed 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.
Duc
lost control of his legs and fingers in a fall and is now considered
partially quadriplegic. He said controlling the robot wasn’t hard on a
good day.
“But
when I’m in pain it becomes more difficult,” he told The Associated
Press through a video link screen on a second laptop attached to the
robot.
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.
A spectator moves out of the way as Mark-Andre Duc, seen on the computer screen, directs a robot at Switzerland’s Federal Institute of Technology in Lausanne, Switzerland, Tuesday, April 24, 2012. AP Photo/Anja Niedringhaus |
While
the human brain is perfectly capable of performing several tasks at
once, a paralyzed 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,” Millan 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.
Rajesh
Rao, an associate professor at the University of Washington, Seattle,
who has tested similar systems with able-bodied subjects, said the
Lausanne team’s research appeared to mark an advance in the field.
“Especially if the system can be used by the paraplegic person outside the laboratory,” he said in an email.
Millan
said that although the device has already been tested at patients’
homes, it isn’t as easy to use as some commercially available gadgets
that employ brain signals to control simple toys, such Mattel’s popular
MindFlex headset.
“But this will come in a matter of years,” Millan said.
Source: The Associated Press
