People with nerve or limb injuries may one day be able to command wheelchairs, prosthetics and even paralysed arms and legs by "thinking them through" the motions.
As researchers overcome the technical and biological hurdles to begin the first human trials, Peter Evans examines how capturing brain output could allow fully paralysed patients to interact with the world.
Harnessing the brain's power
The idea behind the research is to insert a computer between pathways in the brain and the world outside, which have been broken due to neurological injuries or diseases.
At Duke University's Center for Neuroengineering in North Carolina, Professor Miguel Nicolelis has created an artificial bypass to carry brain signals to an activator, which produces the movement the person is thinking about.
Thanks to a tiny implant in the motor cortex, monkeys have been able to control a robotic arm, just by thinking about making the movement.
A step ahead
Researchers at Brown University in Rhode Island have taken things a step further by working with a tetraplegic man.
They have found that the patient's motor cortex still transmits the same electrical signals a non-paralysed person uses to control their muscles, even though the connections themselves are broken.
The research team has captured these signals using microelectrodes, and built the technology to allow him to carry out basic tasks by moving a cursor around a computer screen.
For the patient, carrying out these simple activities represents a significant improvement in the quality of his life.