Robotic arm controlled by paralyzed patients' thoughts

Scientists at Brown University have developed a computer electrode sensor, implanted into the brain, which patients can use to control the movements of a robotic arm.

In collaboration with the Department of Veteran Affairs, Massachusetts General Hospital, and Harvard Medical School, the neurosurgeons at Brown have implanted tiny recording devices into two patients' brains - specifically, into the motor cortex. Both patients are paralyzed (can not move their arms or legs) and unable to speak due to stroke. Each recording device contains about 100 hair-thin electrodes which record neuronal signals in the brain associated with intention to move. The recordings from the devices are relayed to a computer connected to a robotic arm. One of the patients - Cathy Hutchinson - is now able to use her thoughts to make the robotic arm grasp a coffee flask and lift it so she can take a sip. This is the first time since her stroke 15 years ago that she's able to drink unassisted. Her smile in the video below says it all. "People who are paralyzed have their brain disconnected from their bodies.... The idea is to bypass that damaged nervous system; go directly from the brain to the outside world. So the brain does not control the muscles but instead controls machinery or devices such as a robotic limb," says lead researcher John Donoghue in the video. Donoghue is part of the BrainGate project at Brown. In 2006, he led a trial where two patients were able to use their minds to move a computer screen cursor. "There's really a big challenge from moving a cursor on a screen, which slides around in two dimensions, to controlling something as sophisticated as a robotic arm," continues Donoghue. In the future, the researchers hope to develop a wireless version of the system. Eventually, they hope to direct patients' brain signals to their own muscles, so that paralyzed limbs may one day function again.