Swiss scientists are making paralyzed patients walk again

In encouraging news, Swiss researchers were able to obtain nine Spinal cord injuryThree of them had complete paralysis—without any sensation in the legs— walk again.

They were implanted with devices that somehow reconnected the elemental “wire” that connects the impulses that leave the brain and reach the spinal cord. Five months after the trial, all participants finished Realize your own weight and take actionUsing a walker to maintain stability.

Thanks to a gadget Attached to the spinal cordScientists at the Defitech Center for Interventional Neurotherapies in Switzerland, called “NeuroRestore”, managed to do this. Electrically stimulates a specific type of neuron (They are not in the brain, but in the spinal cord) After painstaking mapping work, they were able to determine the “key” to brain-spinal cord communication.

Electrical stimulation restored legs in nine patients.

Everything is based on a paper in the journal Nature Published this Thursday, its title shocks for its classy simplicity: “Neurons that restore gait after stroke”that is, “Neurons that recover gait after paralysis”..

“Spinal cord injury blocks pathways from the brain and brainstem to the lumbar spine, leading to paralysis,” the researchers begin in the text.

And they say: “Here we show it Spatiotemporal epidural electrical stimulation (ESS) lumbar spine used during nerve rehabilitation (NdR: the abbreviation they use for this procedure is EESREHAB) The parade was restored in nine subjects with chronic spinal cord injury”.

How patients were made to walk again

Led by French neuroscientist Grégoire Courtin, the researchers published the first paper in 2018 in which they shared the news of their achievement. Three patients regained their gait.

However, they did not achieve then what they have achieved now: Understand which neurons to stimulate Achieving the ambitious goal: Patients with chronic spinal cord injury can stand up and move their legs. Also, in more severe cases, restore the lost sensitivity of the lower limbs.

According to the work, they proposed a “molecular atlas”, of sorts Neural activation map Supports one’s walking ability.

It was the placement of the device in question that allowed them to draw that basic diagram, which they call at work “Molecular Mapping“Without a doubt, this is the basis for understanding why patients who have been immersed in stimulation have recovered their motor skills.

The neurons behind the ability to walk

It should be clarified that the neurons highlighted in this publication do not (presumably) play a significant role in healthy individuals.

Precisely, the achievement of the work is concrete: the rehabilitation of people with spinal cord injuries involves a specific activity, The risk is different from that of patients who do not have that problem.

This is the case for The inherent complexity of stroke As an event.

As the paper explains, “the neurons that regulate walking reside in the lumbar spine.” For this to happen, “the brain sends commands through a cascade of descending pathways from the brainstem to activate these neurons.”

In the event of an injury, although the neurons located in the lumbar spinal cord are not directly damaged, the effect of “fatigue of essential supraspinal commands” occurs, these neurons become inactive: “The effect of Permanent freeze“.

Gait and electrical stimulation

In the stimuli tested for this work, the researchers “Unexpected decrease in lumbar nerve function During the parade“.

How is it explained? Experts believe that the reduction actually reflects a “selection” of activity Specific neurological subpopulations As said, these patients need to walk.

Although recognizable Organizing neural subpopulations As mentioned, the Swiss scientists make it clear that this is not a finished work: there are many questions about the essence of the neurons in question.

Specifically, the underlying “biological principles” whereby electrical stimulation “engages and remodels the lumbar spine to restore gait.” The principles they agree on “remain unknown”.

For this reason, they conclude, “understanding the contribution of each neural subpopulation to complex behaviors such as walking is a challenge.” A fundamental challenge in neuroscience“.

AS