This mind-controlled robotic arm lets you do two things at once

Eight people have reliably used a mind-controlled robotic third arm to do two things at once. The technology could be used give a helping hand when lifting heavy objects or for tasks that require more than two arms. Participants in the experiment had to learn to control a robotic arm using a brain-machine interface. The robotic arm was placed next to the participants, and they wore two electrodes on the outside of their head to capture brain activity. The arm was then calibrated to pick up on the differences in brain patterns when participants imagined the arm grasping and releasing a bottle.