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A diagram shows how researchers first severed the nerve connection with the monkeys' arms and then reconnected their wrists via a rerouted connection to a single neuron. The monkeys were able to then move their wrists and play the game shown, which earned them treats.  (Source: Chet Moritz et al Nature)
Research are finding that rerouting nerve signals in primates may be surprisingly easy

DailyTech previously covered how monkeys had been wired with brain probes to a mechanical arm, which they learned to control.  Now another experiment has taken such concepts, much farther, reversing paralysis in monkeys through neuron implantation.

Eberhard Fetz, a professor of physiology and biophysics at the University of Washington, led the research.  The researchers began by paralyzing the nerves leading to the monkeys' arms.  They then placed a single wire on a neuron in the monkeys’ neural cortexes.  From there they routed the signal to a single neuron implanted in the monkeys' arm muscles.  The computer detected a specific firing pattern in the brain neuron and would then signal the neuron in the arm.

The electric "re-routing" working surprisingly well and the monkeys regained control of their wrists.  Their new capability was assessed by a simple video game.  The game was controlled by the monkeys' wrist motions.  By moving their wrists, they could move a cursor onscreen and by moving it to a box on the side, they could earn a reward.  With the incentive of the reward the monkeys soon learned to move their wrists, even though the motor cortex neuron was selected at random.

Chet Moritz, a senior research fellow at the University of Washington and coauthor of the researchers' paper states, "We found, remarkably, that nearly every neuron that we tested in the brain could be used to control this type of stimulation.  Even neurons which were unrelated to the movement of the wrist before the nerve block could be brought under control and co-opted."

The research is published in the latest online version of the journal Nature.

Most previous research had focused on complex firing patterns.  This is because typically even moving one arm muscle results from the firing of multiple neurons in a coordinated pattern.  The success of the single neuron approach raises new questions about how exactly the primate nervous system processes signals.

Regardless of the mechanics, the approach works, and Moritz says that it will be very useful as it requires less computing power.  In order to apply the new research to paralyzed patients, more work remains to be done.  Most importantly, the researchers will have to learn to make multiple rerouted muscles fire coordinately as they would in the body in a complex motion such as walking, or picking up an object.

For this reason, Andrew Schwartz, a professor of neurobiology at the University of Pittsburgh, remains a skeptic of the new efforts.  He states, "If your intention is to generate a movement, you have to somehow calculate the effect of all these forces across the arm.  It's not just, 'Activate a muscle and the arm goes where you want.' There's a lot of math involved."

Still, the University of Washington Researchers have moved forward to where one neuron controls two different wrists motions with different firing patterns mapped to each motion and another scenario in which two rerouted neurons each controlled a single muscle (direction of motion) and worked together.  Also they say one spinal cord cell, rerouted, can activate multiple arm muscles.  Moritz states, "Stimulating a single location in the spinal cord will often activate 10 to 15 different muscles in a precise balance."

The risks are also significant.  The electrodes wear down over time.  Also if they protrude out of the skin, there's major risk of infection and disruption in a normal daily environment.  The ultimate goal, the University of Washington researchers say, is miniaturization.  Says Moritz, "We think we may be one step closer to low-power, fully implantable systems."



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RE: Reminds me of Bicentennial Man...
By GaryJohnson on 10/17/2008 12:56:55 PM , Rating: 3
Arg! Another moral/ethical debate on DT. Just stop it. It never goes anywhere productive.

Mick knew this would happen. Don't feed the Mick.


RE: Reminds me of Bicentennial Man...
By JasonMick (blog) on 10/17/2008 1:08:25 PM , Rating: 3
Mwahaha I not only knew this would happen, I knew you would say that. It's true-- I'm secretly Sylar. You found me out. Its nice to get so much credit, you know. :)

Oh and I'd say the real ethical questions in not whether zygot(e) are alive, but whether zeitgeists are alive. I mean that's a very confusing assessment to make... but without it, how can the future of zeitgeist research proceed??


RE: Reminds me of Bicentennial Man...
By masher2 (blog) on 10/17/2008 1:31:20 PM , Rating: 3
> "but whether zeitgeists are alive..."

Either you're making a joke that's above my head, or that word doesn't mean what you think it means.


By JasonMick (blog) on 10/17/2008 3:04:12 PM , Rating: 2
Well I'm being a bit tongue-in-cheek, but if you believed in a collective unconscious, zeitgeists of each era could indeed be alive (or at least the direct action of a living entity), in the sense that they would be the manifestation of some massive entity composed of living matter. ;)

I thought we were getting a little bit too serious debating whether there's consciousness/a spirit in zygotes, something that's impossible to prove or disprove. We can't even prove such things in adult humans, so to argue about zygotes is an exercise in futility.


RE: Reminds me of Bicentennial Man...
By Seemonkeyscanfly on 10/17/2008 1:45:35 PM , Rating: 2
zygote zy·gote (zi'got')
n.
The cell formed by the union of two gametes, especially a fertilized ovum before cleavage.
The organism that develops from a zygote.

Zeit·geist (tsit'gist', zit'-) Pronunciation Key
n. The spirit of the time; the taste and outlook characteristic of a period or generation: "It's easy to see how a student . . . in the 1940's could imbibe such notions. The Zeitgeist encouraged Philosopher-Kings" (James Atlas).

(new things I learned today.... thanks)

Now with that in mind... Doctors, paramedics, Nurses, and such determine someone is dead when their heart stops beating (let us not talk about the berlin heart or things like this device). So, if we use that thought the reverse should be true, if you have a beating heart you are alive, maybe brain dead but alive. I do not think either a zygote or zeitgeists has a heart let alone a beating heart. So, in my book they are not a creature or thing that can be alive from the start. They might be part of a live thing, but not living on their own.

OK, so what are you going to tell me that I'm missing in my thought process?


RE: Reminds me of Bicentennial Man...
By foolsgambit11 on 10/17/2008 3:32:07 PM , Rating: 2
Right, and scientists call something that leeches off another life form a parasite. Doctors help cure you of parasites (even non-life-threatening ones). If a zygote isn't viable outside of the womb, it is, ipso facto, a parasite. All doctors should offer treatment upon discovery of pregnancy. It is then the woman's choice whether to accept treatment or deal with the consequences.

OK, so what are you going to tell me that I'm missing in my thought process?

(I'm at least partially playing devil's advocate here - that is, I don't buy into this argument, but I support a woman's right to choose.)


RE: Reminds me of Bicentennial Man...
By Myg on 10/17/2008 4:20:52 PM , Rating: 2
Based on the logic of your arguement, a human being is a parasite from the moment of conception to death of old age.

The underlying fact is, and its often lost; is that we rely on other humans and creatures around us just like a 'parasite' does.

Its a web of interconnectivity that is unescapable and dangerous to the very fabrics of society if not accepted.

To call a spoon a fork definetly wont help you chose from the "primordial soup" any easier.


By foolsgambit11 on 10/18/2008 1:45:50 PM , Rating: 2
Oh, come on. My conflation was humorous and pointed (if I may say so). Your conflation ignores a major portion of the definition of a parasite. A parasite has a single host. It's also humorless and all new-agey. Our relationship with other humans and creatures (with the exception of the ones we eat, I suppose) is more a mutually symbiotic one, anyway.


RE: Reminds me of Bicentennial Man...
By William Gaatjes on 10/19/2008 4:09:08 PM , Rating: 3
Actually there has been some research done where the zygote in a later state starts to function as a parasite but more similair like cancer does. I am still searching where i found that.

On a side note, I noticed that some egg laying animals do not have cancer like diseases. Maybe the ability to get cancer is someting only mammals have because mammals give living birth ? Maybe there are similair genes used by cancercells to hide themselves when they become an organised like a tumor. For those that say men can have tumors too, we have the same immune system as women only with women, in the womb the embryo and the placenta has some way of fooling the mothers immune system.

Here are some links for the interested :

http://research.yale.edu/ysm/article.jsp?articleID...

http://www.thenakedscientists.com/HTML/articles/ar...

http://www.sciencedaily.com/releases/2008/06/08061...

search for this text on the website below :Why_isnt_an_implanted_embryo_rejected_by_the_mothe r_in_the_way_that_an_allograft_is

http://www.nurseminerva.co.uk/pregnancy.htm#Why_is...

I don't know, i am cetainly not an expert but i do find it fascinating.


By William Gaatjes on 10/19/2008 4:11:48 PM , Rating: 2
yay i thought it up, and finished reading the sciencedaily article and the researcher says it too. I am happy :).


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