Regaining movement in paralyzed limbs may be possible in a few years time. In an article published in Nature, scientists at the University of Washington in Seattle, under Chet Moritz, have used signals from just one cell in a monkey's brain to restore movement to a paralysed muscle in the monkey's wrist.
Previously, scientists have been able to train monkeys to move robot arms using signals from electrodes in the monkeys' brains. This involved decoding the activity of tens of neurons at a time to replicate actions such as grasping, and required considerable computing power.
The scientists first implanted electrodes in the motor cortex of two monkeys. Each electrode picked up signals from a single neuron, and those signals were routed to a computer. The neuronal signals controlled a cursor on a screen, and the monkeys were trained to move the cursor using only their brain activity.
They then temporarily paralysed the monkeys' wrist muscles using a local anaesthetic. They re-routed the signals from the electrodes to deliver electrical stimulation to the wrist muscles, and found that the monkeys could control their previously paralysed muscles using the same brain activity. Amazingly the monkeys learnt to do this in less than an hour. Not only that, but it improved with practice.
This is further evidence of the astounding ability of the brain to adapt, as it does not matter what the previous function of that brain cell was, it can be trained anew to sere a new purpose. Even if the neuron was unrelated to the to the activity of the paralysed muscles.
There are still many steps to a fully functioning prosthesis. One muscle moved with one unrelated neuron, after one hour's practice, is a stunning breakthrough. The development of a multi muscled, multi jointed limb is obviously far more complex, but this work shows it is now doable.
As the technology improves the hardware will very likely shrink. The vision is a device small enough to implanted under the skin, which directs the impulses to the prosthesis. Clinical trial for humans are many years away, but the basic technology works.
It has long been know that brain activity, such as crossword puzzles, playing chess, studying new languages etc., help keep aging brains young. Now it has been shown that searching on the Internet does wonders for old age pensioners, keeping their minds active and healthy.
Searching on the Internet may train the brain according to the research which appeared in the American Journal of Geriatric Psychiatry.
Researchers at the University of California Los Angeles, led by Dr. Gary Small, an expert on aging studied people, between the ages of 55 and 76, doing Web searches while their brain activity was being recorded.
He found that people new to the Internet, read the pages superficially, while those who are familiar with the Internet engage in a much deeper level of brain activity, as they actively searched the web sites.
In the aging brain, atrophy and reduced cell activity can take a toll on cognitive function. Activities that keep the brain engaged can preserve brain health and thinking ability.