A System That Reverses Paralysis

[longknife]

The tech behind a device that might be able to reawaken connections between the brain and the body.

There are so many medical advances everywhere we turn it is almost impossible to comprehend what lies in our future.

Read more @ How It Works: A System That Reverses Paralysis | Popular Science

 

[waltky]

Brain-to-computer technology gives paralyzed California man the chance to walk...

Brain-computer link gives paralyzed California man the chance to walk
Fri, Sep 25, 2015 - A brain-to-computer technology that can translate thoughts into leg movements has enabled a man paralyzed from the waist down due to a spinal cord injury to become the first such patient to walk without the use of robotics, doctors in Southern California reported on Wednesday.

The slow, halting first steps of the 28-year-old paraplegic were documented in a preliminary study published in the UK-based Journal of NeuroEngineering and Rehabilitation, along with a YouTube video. The feat was accomplished using a system that allows the brain to bypass the injured spinal cord and instead send messages through a computer algorithm to electrodes placed around the patient’s knees to trigger controlled leg muscle movements. Researchers at the University of California said the outcome marks a promising, but incremental achievement in the development of brain-computer interfaces that might one day help stroke and spinal injury victims regain some mobility.

Study co-author An Do said clinical applications were many years away. Results of the research still need to be replicated in other patients and greatly refined. Nevertheless, the study proved it possible “to restore intuitive, brain-controlled walking after a complete spinal cord injury,” said biomedical engineer Zoran Nenadic, who led the research. The steps were taken a year ago by the experiment’s subject, former graduate student Adam Fritz, who injured his back in a motorcycle accident. Fritz propelled himself over a distance of 3.6 meters across the floor of UC Irvine’s iMove Lab, though his weight was partially supported by an overhead suspension harness and a walker he grasped to keep his body upright, researchers said.

Former graduate student Adam Fritz demonstrates a brain-computer interface experiment at the University of California iMove Lab in Irvine

The weight support was necessary because the patient lacked any sensation in his legs or feet, Do explained. Still, the experiment built on earlier UC Irvine studies in which brain signals were transmitted to a robotic prosthesis attached to the patient’s legs to produce movement, Do said. The latest study, which began about five years after Fritz became paralyzed, involved months of mental training in which he practiced thinking about walking to produce necessary leg-moving brain waves.

Those signals were then picked up by an electroencephalogram (EEG) he wore as a cap and were transmitted to a computer for processing by a special algorithm that could isolate the messages related only to leg motion and convert them to signals that would stimulate the patient’s muscles to walk. Researchers hope to refine the technology by miniaturizing the EEG component enough to be implanted inside the patient’s skull or brain, allowing for clearer reception of the neural messages and perhaps the delivery of pressure sensation from sensors in the foot back to the brain.

Brain-computer link gives paralyzed California man the chance to walk - Taipei Times

 

[waltky]

Peripheral nerve cells can be coaxed to repair damaged axons...

Nerve Cells Can Be Switched on to Repair Damage
20 Sept.`16 - Scientists at the University of Wisconsin have found a way to coax peripheral nerve cells into repairing damaged axons. Peripheral cells extend outside the central nervous system into the arms and legs and are responsible for sensation. They contain long fibers known as axons that transmit impulses from the brain. They can be damaged in diseases such as diabetes, causing pain.

The axons are surrounded by a protective sheath called myelin, a fatty insulation that speeds electrical signals from the brain. Myelin is created by Schwann cells, but researchers have discovered that Schwann cells can also stimulate nerve regrowth. They conducted an experiment in mice with both intact axons and axons which had been cut. Using a method for switching on genes, they saw Schwann cells become more active, but only in the injured rodents. They went into a repair mode that stimulated nerve regrowth. This clean-up, as researchers call it, began within days of the injury.

Supportive Schwann cells (green) surround the conductive axon (purple) of a neuron in the peripheral nervous system in this artificially colored image.​

As part of the clean-up process, the Schwann cells send signals that enlist blood cells to help in the repair. During this time, the myelin begins to dissolve to make room for the axonal repair. After the axons are on the road to recovery, a new myelin sheath begins to form over the regenerated fibers. The scientists identified a particular pathway that switches the Schwann cells on or off. They suggest drugs may some day be available to activate the repair program. A report on axonal regeneration was published in The Journal of Neuroscience.

Lead researcher John Svaren, a professor of comparative biosciences at the University of Wisconsin, says it’s not clear that this single on-off pathway works to regenerate all axonal nerve cell damage. But he’s hopeful that it’s a key repair mechanism, not only within the peripheral nervous system but for nerve damage within the brain. Until now, Svaren says scientists have thought of the Schwann cell as a “static entity,” with only one function: producing myelin. But he is excited that the cells can be coaxed to become “first responders” in helping to repair the peripheral nervous system.

Nerve Cells Can Be Switched on to Repair Damage