It sounds like science fiction but “thought control” — communicating commands from a human brain directly to an external device — is happening here and now. It allows patients with cerebral palsy, spinal cord injuries, or those recovering from a stroke, to move the cursor on a computer screen, manipulate a robotic arm or navigate a wheelchair. There’s a considerable amount of R&D taking place around these so-called brain-computer interfaces (BCIs) and the ways in which they can allow people to control their environment.