Arm and hand movements have been RESTORED in paralyzed monkeys with an external stimulator that disables the spinal cord, which could help millions of people regain their mobility.
- Scientists have restored the movements of the arms and hands in paralyzed monkeys
- This was done by exposing the spinal cord of the animals to an external simulator.
- The monkeys were implanted with electrodes along their spines that were connected to an external stimulator the size of an eraser on the tip of a pencil.
- The animals were also implanted with brain implants that track voluntary movements.
Scientists restored the movements of the arms and hands of paralyzed monkeys by turning off their spinal cords.
The successful experiment allows the University of Pittsburgh team to begin human trials, and patient recruitment is underway.
For preclinical testing, monkeys were implanted with electrodes along their spines that were connected to an external stimulator the size of an eraser on the tip of a pencil.
The animals have also been given brain implants that track voluntary movements.
When the brain implants detected the animal’s intention to move the arm, the stimulator sent small electrical shocks up the spinal cord to the muscles in the arm and hand.
The video of the experiment shows that the monkey can’t reach the treat, but when the stimulator hits its spinal cord, it can reach for the food and grab it.
Breakthrough study gives hope to more than five million people paralyzed by spinal cord injury or stroke.
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Scientists restored the movements of the arms and hands of paralyzed monkeys by turning off their spinal cords. The picture shows a paralyzed monkey before its spinal cord was damaged. He tries to reach for the treat, but he can’t move his hand.
The analysis showed that while not enough to fully restore hand function, stimulation significantly improved accuracy, strength, and range of motion, allowing each animal to move its hand more efficiently.
Importantly, the animals continued to improve as they adapted and learned to use the stimulation.
Co-author of the first study, Dr Sarah Conti of Harvard Medical School in Boston, told SWNS: “Our protocol consists of simple stimulation patterns that are triggered by detecting the animal’s intention to move.
“We don’t need to know where the animal wants to go. We only need to know that they want to move, and extracting this information is relatively easy.
The stimulation hits his spinal cord. The monkey can raise his hand for a treat.
“Our technology can be implemented in clinics in many ways, potentially without brain implants.”
The team began this work with the goal of developing a technology that activates the remaining healthy nerves that connect the brain and spinal cord to control arm muscles with external stimuli – a difficult task to say the least.
Senior author Marco Capogrosso, assistant professor of neurological surgery and member of the Pitt Rehabilitation and Neural Engineering Laboratory, said in statement“In order to execute even the simplest hand movement, our nervous system must coordinate hundreds of muscles, and it would be very difficult to replace this complex neural control with direct electrical muscle activation outside of the laboratory.”
“Instead of stimulating the muscles, we simplified the technology by developing a system that uses surviving neurons to re-establish communication between the brain and hand with special spinal cord stimulation pulses, potentially allowing a person with paralysis to perform daily tasks. ‘
Here the monkey is able to grab a treat, to which it also moves towards the mouth.
The monkeys were given brain implants that detect electrical activity in areas that control voluntary movement. When they sensed the animal’s intention to move the hand, a small array of electrodes connected to a stimulator the size of a pencil eraser were turned on.
To test the technology, the researchers worked with paraplegic macaque monkeys who were trained to reach, grab and pull a lever to get their favorite treat.
They were equipped with brain implants that detected electrical activity in areas that control voluntary movement.
When they sensed the animal’s intention to move the hand, a small array of electrodes connected to a stimulator the size of a pencil eraser was turned on.
It was placed over the nerve roots extending from the spinal cord to the muscles of the arm and hand.
Co-author, first co-author Dr. Beatrice Barra, currently at New York University, said in a statement: “To take a step back and solve a very complex clinical problem from a different and simpler point of view compared to everything that has been done before, opens more clinical options for people with paralysis of the arms and hands.
“By creating technology based on the nervous system that mimics what it’s naturally designed to do, we’re getting better results.”
Electrical spinal cord stimulation, described in the journal Nature Neuroscience, will be tested on paralyzed stroke patients in the US later this year.