A 26-year-old man in the United States, paralyzed for the past five years from an injury to his upper-middle spinal cord, has been able to walk with the aid of an electrical system that connects his brain and legs, bypassing his injured spine. The experimental system is appropriate for people who have spinal cord injuries to their upper to lower-middle backs and who do not have other major problems.
Before he could try out the system, the man had to go through some muscle reconditioning to regain some strength in preparation for standing and walking. The system also required him to wear a cap with electrodes, a backpack with an amplifier, a contraption called a Parastep that electrically stimulate the legs, and a belt with a controller for the Parastep.
For each step, the system worked in a series of relayed information, beginning with the brain. When the man tried to move his legs, the signal his brain sent passed through the electrodes to the amplifier. The amplifier passed the message wirelessly to a computer. The computer analyzed the message, concluded that it said ‘walk’, and passed the signal to the controller.
The controller then told the Parastep to stimulate the leg to step. The brain signal bypassed the unresponsive spinal cord, looped through the computer, and went straight to the man’s legs. The result was that he could walk on his own for about 4 meters. The scientists involved in the experiment agreed that the system is a little complicated and the technology a bit cumbersome. Nevertheless it did provide proof that it was possible to elicit prolonged benefit for a broad range of persons with paraplegia, if controlled correctly.