New technique paves way for thought-controlled prosthetic hands

Researchers from the University of Houston have created an algorithm to allow for the creation of a prosthetic hand that can be controlled using thoughts alone.

The method uses non-invasive brain monitoring to capture brain activity involved in grasping an object. A brain-machine interface (BMI) system was then created based on this insight to harness a subject's intentions and allowed them to successfully grasp objects.

A 56-year-old man whose right hand had been amputated was used to trial the new method. With the system in place, he was able to successfully grasp objects including a water bottle and a credit card, gripping the selected objects with an 80 percent success rate.

Previous methods make use of either surgically implanted electrodes or myoelectric control, which relies upon electrical signals from muscles in the arm. This new process instead measures brain activity via scalp electroencephalography (EEG).

In doing so, it avoids the risks of surgically implanting electrodes, while offering a new option for those for whom myoelectric systems are not an option, since they require that neural activity from muscles relevant to hand grasping remain intact.

The scientists said this research shows that it is viable to use scalp EEG signals "to extract detailed information on intended grasping movements to various objects in a natural, intuitive manner".