Neuroscience: Brain control of a helping hand

Published by John F. Kalaska on Nature journal (28/05/08)

Paralysed patients would benefit if their thoughts could become everyday actions. The demonstration that monkeys can use brain activity for precise control of an arm-like robot is a step towards that end. Strokes, spinal-cord injuries and degenerative neuromuscular disease all cause damage that can severely compromise the ability of patients to use their muscles. The loss of mobility and independence that results from such motor deficits takes a devastating toll on their quality of life. Medical research is striving on many fronts to reverse the disease or injury state of such patients. Meanwhile, other approaches are needed to enhance their quality of life. Often, the patient's condition leaves intact parts of the cerebral cortex involved in voluntary motor control, including the primary motor cortex, premotor cortex and posterior parietal cortex. These patients are still able to produce the brain activity that would normally result in voluntary movements, but their condition prevents those signals from either getting to the muscles or activating them adequately. In such cases, one possible solution is to let the subjects think about what they would like to do as if they were mentally rehearsing the desired actions, record the resulting brain activity, and use those signals to control a robotic device. The development of such brain–machine interfaces (BMIs), or neuroprosthetic controllers, is being pursued in several laboratories. Click for more...