A sticking plaster may appear to be a grossly inadequate treatment for a paraplegic. Attach a few electrodes, though, and a device that resembles such a dressing could help translate into actions the thoughts of people who are paralysed. In 2008 a practical version will be shown to work and the first individuals will be recruited to try them for real.
Paralysis is a breakdown in communication. The brain does not t0rget how to ride a bicycle. 41. ____________________________________.
John Donoghue of Brown University in Rhode Island has been working on how to restore that link. He has shown that the technology he has developed works, albeit only for a handful of people who were prepared to endure having a tangle of wires dangling from their heads. In 2008 Mr. Donoghue and his colleagues will turn their device into something that looks like a hearing aid and whose use could become almost as routine.
42. ______________________________. When the nerve cell fires, this electrical activity will be picked up by the wire and conveyed to the silicon chip.
43. ____________________________________. Power will come via an inductive coil placed under the scalp and next to another on top of the scalp, which will be attached to a battery. This, and a computing unit worn on a belt, will be the only parts visible outside the body. Ultimately the team intends to implant the computer unit in the chest, connected to the brain by a fibre-optic cable.
The researchers reckon their device will be able to direct a motorised wheelchair or move a robotic hand. But they also want to restore to paraplegics the use of their own bodies. 44. ______________________________. Connecting the two systems together would mimic the way in which the body normally works. But restoring useful movement to paraplegics involves more than making muscles work once more. It also means restoring a capability that most able-bodied people do not realise they have: the use of sensory feedback to fine-tune actions. 45. __________________________________________.
In order to achieve this, in 2008 Mr. Donoghue and his colleagues will develop their system to run in reverse. Because the monkeys used in the tests will not be paralysed, the implant will not only broadcast what the brain is doing but also eavesdrop on what happens to the nerve cells when they are receiving information. This could then be mimicked in people. The idea is that paralysed people could operate, say, a robotic hand with sensors that collect information about the pressure and temperature they encounter and convey these data back to the brain. That is, the human brain will be stimulated to feel what the robot senses. Not bad for a device that looks like a sticking plaster.
[A] The researchers will implant a silicon chip the size of a small button into the brains of monkeys. The chip will be fitted with an array of 100 thread-like gold wires, each of which will be attached to a nerve cell in the brain
[B] Hence their involvement with Hunter Peckham of Case Western Reserve University. He is developing a system which electrically stimulates muscles to make them move once again.
[C] Years after paralysis has struck, the same nerve cells fire when someone is thinking about moving ; it is just that the rest of the body does not receive the message.
[D] There are many kinds of sticking plasters, which are now in wide use in many countries. But sticking plasters are not very adequate to treat paraplegics and paralytics.
[E] Reach out to pick up a cup of hot tea from a vending machine and, as your hand touches the cup, it subtly adjusts its grip so that enough strength is used to lift the cup without crushing it and burning your fingers.
[F] The next step will be to transmit this information from the skull to the outside world. A second device will be attached to the silicon chip to do this. It will transmit data through the skin using pulses of infra-red light, just like a remote control.
[G] A robotic hand is equipped with sensors, which are mainly used to collect related information and transmit it to the outside chip. Then this chip will process the message and inform the paraplegic to move his or her muscles.
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