Moving without a spinal cord is no longer fantastic

An electronic interface between the brain and muscles has been created

Leonid Popov, Membrane based on Northwestern Medicine:
New Brain-Machine Interface Could One Day Help Paralyzed IndividualsThe new technology allows the brain to arbitrarily control the muscles of the limbs, bypassing the spinal cord.

Potentially, it will allow the paralyzed patients to regain mobility again. So far, however, the system has been tested only on animals.

Neurophysiologists from the Northwestern University School of Medicine built a system that allowed monkeys to act quite accurately with a paralyzed hand (temporary paralysis was achieved by injecting a drug that blocks the passage of nerve signals).

To begin with, scientists implanted tiny multielectrode implants into the animals' brains that recorded the activity of about 100 neurons. The experimental primates were given a task – to pick up a ball at the end of a curved tube and throw it again exactly into the hole.

During these tests, the computer recorded the signals that the brain sent to the hand. Next, the researchers developed a decryption algorithm that allows the activity of only hundreds of key neurons to restore commands issued to muscles.

Then, with the help of local anesthesia, the scientists interrupted the connection of the brain with the hand in the experimental monkeys. The experimenters connected a neuroprosthesis to the arm. He sent weak electrical impulses to the muscles in accordance with the commands of the computer, which, in turn, deciphered the motor signals of the brain on the fly and formed the correct messages in just 40 milliseconds.

The scheme of the experiment. The creators of the system believe that it will be possible to refine it over time
and test it on people with damaged spinal cord
(illustration by Miller Lab of Limb Motor Control).

Although with such a roundabout way of control, the accuracy of the monkeys' movements decreased, they quickly learned to perform all the same tasks with a ball. The authors of the work say that the situation here resembles the moment when you pick up a new computer mouse or a new tennis racket – at first the movements seem unusual, but soon the brain adapts to the new environment, learns how to act correctly with a new object.

Portal "Eternal youth" http://vechnayamolodost.ru23.04.2012