Signals that start in the brain are supposed to travel down nerves in the spinal cord to muscles, but breaks in the nerves interrupt them. Patching the breaks with new wires, jumping over the cut in the phone line, should restore communication.
The electrodes were designed to pulse and stimulate muscle fibers so that the muscles could pull on tendons in his hand.If it all worked, a man who was paralyzed from the chest down would think about wiggling his finger, and in less than one-tenth of a second, his finger would move.They would bypass his broken spinal cord and put a computer in its place.
The 2.5-ounce (72-gram) device began emitting electrical current at varying frequencies and intensities, stimulating dense bundles of neurons in the spinal cord. Three days later he stood on his own. In 2010 he took his first tentative steps.The team wasn’t as optimistic about their next patients – unlike Summers, they didn’t have any sensation in their legs – and they were surprised when four men who were paralyzed from the chest down were able to voluntarily move their legs and feet after being implanted with the device. While the men were not able to walk, the experiment was hailed as a major success and offered new hope for the more than 6 million paralyzed Americans.
What would you give for a retinal chip that let you see in the dark or for a next-generation cochlear implant that let you hear any conversation in a noisy restaurant, no matter how loud? Or for a memory chip, wired directly into your brain's hippocampus, that gave you perfect recall of everything you read? Or for an implanted interface with the Internet that automatically translated a clearly articulated silent thought ("the French sun king") into an online search that digested the relevant Wikipedia page and projected a summary directly into your brain?