Thursday, 10 November 2016

Thinking about Walking again

Research in Multiple Sclerosis can learn from other disciplines and when it comes to repair and neurorestoration, dealing with spinal cord injuries is light years ahead of MS. 

The reason is simple you have the insult that causes the problem and then healing occurs but in MS the insult just keeps on coming. Thankfully new MS drugs are making impact on stopping the damage from coming, but for some this is all too late and we need to regain lost function. Many believe that this is going to come from stem cells, but the hype has yet to deliver. Another approach is to gain a helping mechanical hand and so I report away from MS and onto  animal experiments .

Capogross et al. A brain–spine interface alleviating gait deficits after spinal cord injury in primates  Nature 539, 284–288 (10 November 2016) doi:10.1038/nature20118.

Spinal cord injury disrupts the communication between the brain and the spinal circuits that orchestrate movement. To bypass the lesion, brain–computer interfaces have directly linked cortical activity to electrical stimulation of muscles, and have thus restored grasping abilities after hand paralysis. Theoretically, this strategy could also restore control over leg muscle activity for walking. However, replicating the complex sequence of individual muscle activation patterns underlying natural and adaptive locomotor movements poses formidable conceptual and technological challenges. Recently, it was shown in rats that epidural electrical stimulation of the lumbar spinal cord can reproduce the natural activation of synergistic muscle groups producing locomotion Here we interface leg motor cortex activity with epidural electrical stimulation protocols to establish a brain–spine interface that alleviated gait deficits after a spinal cord injury in non-human primates. Rhesus monkeys (Macaca mulatta) were implanted with an intracortical microelectrode array in the leg area of the motor cortex and with a spinal cord stimulation system composed of a spatially selective epidural implant and a pulse generator with real-time triggering capabilities. We designed and implemented wireless control systems that linked online neural decoding of extension and flexion motor states with stimulation protocols promoting these movements. These systems allowed the monkeys to behave freely without any restrictions or constraining tethered electronics. After validation of the brain–spine interface in intact (uninjured) monkeys, we performed a unilateral corticospinal tract lesion at the thoracic level. As early as six days post-injury and without prior training of the monkeys, the brain–spine interface restored weight-bearing locomotion of the paralysed leg on a treadmill and overground. The implantable components integrated in the brain–spine interface have all been approved for investigational applications in similar human research, suggesting a practical translational pathway for proof-of-concept studies in people with spinal cord injury




Scientists have used wireless implants to restore movements but that required a prosthetic limb or a mechanical exoskeleton. This research uses a new brain-spine interface to wirelessly relay information with no cumbersome technology.

When the nervous system is fully functioning, a region of the brain called the motor cortex sends signals that travel down the spine until they reach a neural network controlling movement. The nerves then decode the instructions and activate muscles in the legs to produce walking movements.
Spinal cord injury, just like MS, stops the signal from reaching its destination. However with the interface, the implant picks up the brain activity, sends it to a computer that decodes the signals, and relays those walking instructions to a spinal cord stimulator embedded in the lumbar region.
There has yet to be human testing of the interface, and it's not clear whether it would work on people with severe spinal cord damage. The monkey in the study had a small lesion and would have eventually regained its motor functions on its own. 
Usually with physical therapy, a patient has to re-learn how to walk. In this study, the monkey was able to move  
Amazing click here to go to the Nature website to watch a video. 
However what is telling is that this research invented in Europe was done in China, where there is less regulation.  This is the sorry state of science. Likewise, in another story in this weeks Nature almost all large UK drugmakers slashed in-house research jobs in discovery to outsource it out of the UK to the east and west.
Animal studies in MS are likewise going the same way:-(

18 comments:

  1. This is not a good solution for MS, and less regulation in such research involving a lot of animal suffering is not desirable.

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    1. We share your concerns, working in the UK where animal welfare regulation is probably the most rigorous in the world. Certainly nowhere near as rigorous in other countries.

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    2. I'm worried that this Brexit-baloney is going to break down the UK's regulation. I don't expect researchers with a conscience like you to exploit this, but some might/will.

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    3. Problem is that we are being killed off. I have just been asked to write a piece on "EAE experiments should not be funded-No" I would have course been best place to write EAE experiments should not be funded- YES as I know where the achilles heels are.

      I heard of someone in UK not getting ethical permission to do MS work (could be that it was a rubbish application) but goes to show it is not a rubber stamp.

      However, I have had to wait many, many, many many months to do something which was all about 3Rs benefits to the beasties and the Vet said it was a good idea but am caught in red tape with Home orifice sorry Office:-).

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    4. The Continental Europeans may be happy with Brexit, the UK was been leading many aspects of the EU legislation in animal welfare...with Brexit it may go back to we dont give a s**t attitude from some places.

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    5. I think there is as much - if not more - caring about animal testing in Germany. Certainly when it concerned cosmetics.

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    6. We stopped doing cosmetic testing in animals in the UK some time ago.

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  2. Can't wait for someone to hack that signal :)

    Remote-controlled humans roaming the street!

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  3. I have trouble walking because of drop leg and drop foot. So messages are not getting from my brain to the muuscles in my legs so that I can walk.

    In addition I have a very bad sense of balance when I am walking. Is that not caused by the balance sensors in my feet so being able to send messages back to the brain. Lots of people with MS have balance issues. Will this system be able to address the balance problem?

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    1. Balance is about movement of muscles to maintain position so don't see why not in the future....your internal gyroscope is having a few problems this is about getting the fine tuning back.

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    2. If a person has only a spinal injury, I could see this system working (in theory only). But a person with MS normally has brain damage as well, and this certainly isn't going to be helped by having an implant inserted with inevitable associated tissue damage. I was under the impression that balance issues are associated with damage to the cerebellum. This system can do nothing, ziltch, nada, nichts for brain issues. Furthermore, a person would surely have to be very careful not to fall over and knock their head - horror visions of a dislodged implant. There will be infection complications. And electrical interference could be an issue, e.g. when using a microwave. And my wireless router produces high frequency sound that I can hear - I have good hearing. I am very glad the router doesn't have to be on my head.

      I think that this idea is a load of bunkum, false hope.

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  4. "There has yet to be human testing of the interface, and it's not clear whether it would work on people with severe spinal cord damage. The monkey in the study had a small lesion and would have eventually regained its motor functions on its own."

    So...

    (1) Creating an injury that will heal without intervention does not recapitulate the pathology that they are trying to correct.

    (2) In a human with single leg paralysis, would a long-term significant improvement in quality of life be achieved by:

    (a) implantation of devices requiring: delicate neurosurgery with associated risk, likely regular replacement requiring further surgery & recovery & rehab, and the potential for interference in the system by nefarious individuals (who wants their implants hacked?)

    or

    (b) prosthesis (with or without amputation), and rehabilitation?

    The translational benefit of making a sentient animal suffer in this manner, is what, exactly?

    Not in my name, thanks. Not in my name.

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  5. (1) This is the basis of most remyelination models,,should we stop them?
    The remyelination models used have no chronic inflammation, massive astrogliosis like chronic EAE which has never been done.

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  6. Well, MD, that's a different discussion entirely. Saying that, I imagine I am not alone in wishing that far more effort was invested in developing more disease-relevant and species-relevant models, than throwing tax-payer's money at flawed models that result in limited clinical benefit.

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  7. I would be very happy if tax payers money was sent my way.

    Seems to be spent on esoteric stuff.

    As I had said almost as many times as ProfG has said brain health the models are only as good as the people who use them.

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  8. MD,
    Taxpayers' money consistently comes your way. Who pays your salary? The University via HEFCE? Or is is grant maintained?
    Where do your research grants come from? Research Councils? Charities? Pharma? RCs and charities are directly funded by the taxpayer.
    Pharma makes money from their customers - healthcare providers - funded by the taxpayer.
    Ultimately all medical research is funded by the taxpayer, either directly or indirectly.

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    1. This is a pedantic wiggle . Paying my salary is not paying for the research. You know that. Much of our work is funded by charity not central government which is where your actual tax money goes...I personally do not view charitable donation as tax money. But if you accept that anyone with sufficient money pays tax...unless you are a multinational :-) then it is everyone so why distinguish a taxpayer.Therefore doing or not doing animal is not about tax it is about personal opinion.

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