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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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moral issues
By mattclary on 10/17/2008 2:05:53 PM , Rating: 4
First, let me say that the PETA I belong to is "People Eating Tasty Animals"

With that said... Wow... Doesn't it creep anyone out that they intentionally paralyze these monkeys? To me, paralysis is a pretty horrible fate, even if it is "just" one appendage. I am not against animal testing in general, but I'm just not sure how I feel about this.




RE: moral issues
By themengsk176 on 10/17/08, Rating: -1
RE: moral issues
By InvertMe on 10/17/2008 2:43:43 PM , Rating: 5
You didn't even read the OP did you? You just wanted to lash out on the internet huh? Pretty safe world behind your keyboard.


RE: moral issues
By JonnyDough on 10/18/2008 3:33:50 AM , Rating: 3
I don't know about his keyboard, but I suspect my keyboard of hiding WOMDs. If I don't shoot Osama Bin Laden on this banner ad soon, I'm likely to be blown to shreds. Gosh this is hard.


RE: moral issues
By ShaolinSoccer on 10/17/2008 3:12:20 PM , Rating: 3
Kinda makes you wonder whether or not these people who toture animals in the name of science ever feel bad about it? Or do they just feel nothing at all? If they take pleasure in it then that's really disturbing...


RE: moral issues
By PharmD on 10/18/2008 11:54:12 AM , Rating: 5
The researchers injected drugs into arm muscles of monkeys to induce temporary paralysis, then asked them to play a familiar video game.

Read this article on a website not titled "Daily Tech" and you might find out the researchers DID NOT take a baseball bat to the monkey's spine. They just used drugs very similar to a pregnant women getting nerve block to deliver a child.

"temporary" = "reversable"

/sigh

- PharmD


RE: moral issues
By Justin Case on 10/18/2008 1:16:36 PM , Rating: 3
Ah, but is...

"reversable" = "reversible"

...? ;-)


RE: moral issues
By robinthakur on 10/23/2008 1:03:41 PM , Rating: 2
Or perhaps they don't see it as torture, they see it potentially curing human beings in the future who cannot walk. Long shot here...You seem to have an unfairly low opinion of scientists when practically everything in your world has been invented by them including the anti-biotics that stop you from dying from serious bacterial infections, and the innoculations which have wiped out measles, mumps, rubella, polio etc. like without scientists would be a scarily luddite and dangerous place.


RE: moral issues
By cscpianoman on 10/17/2008 3:59:28 PM , Rating: 5
We do a lot of things to animals that you may not be aware of. We actually have specially bred rats that are homozygous on all alleles (white lab rats) and we do all sorts of things to them. We give them cancer, we test drugs, we paralyze them, we feed them select foods, we hook up probes and all in the name of science.

We do this so we don't have to on humans and it is the choice of which is better ethically. I may have a drug with the potential to cure HIV, but I can't give it to a human without knowing the potential side-effects or if it will even work. If I test it in rats, actually in this case it would probably be dogs, first and there are no side effects and the disease is removed from the animal, then I can take it humans.

There are tons of laws in place to protect these animals. It boils down to whether or not there is a scientific purpose behind the treatment. IF there is a valid reason for it then you can perform the experiment, if not then it is animal cruelty.


RE: moral issues
By JonnyDough on 10/18/08, Rating: 0
RE: moral issues
By Spivonious on 10/18/2008 10:11:22 AM , Rating: 5
Actually it was the fleas on the rats that spread the plague.


RE: moral issues
By MrPoletski on 10/19/2008 7:26:02 AM , Rating: 1
If you don't care about rats, then you should read this daily mail article about....

SURFING RATS

http://www.dailymail.co.uk/news/worldnews/article-...

ZOMG!


RE: moral issues
By ImSpartacus on 10/18/2008 10:05:11 AM , Rating: 5
I think it all boils down to what you value. Do you value humans or animals more?

There's no right or wrong answer, it is an opinion. That said, I think it is pretty unanimous with most cultures of the world that humans are valued more than animals. Does that make it right? No, but that's how it is.

Ethics are relative.


RE: moral issues
By jkresh on 10/17/2008 4:31:37 PM , Rating: 2
not having read the article I can't be sure, but I would assume that the arm paralyses for the monkeys was temporary (if it were rats or something similar paralyzing them for research would not be uncommon, but monkeys are generally better protected).


RE: moral issues
By snownpaint on 10/17/2008 6:02:21 PM , Rating: 2
Most likely for a control factor. You sever the nerve coming out of the spinal cord or near the joint.. You don't want any false positives..


RE: moral issues
By TSS on 10/17/2008 7:15:56 PM , Rating: 4
meh. morals are double standards.

if in 20 years we hold a memorial service for these monkey's, where flowers are laid down by people who used to be paralyzed but now, thanks to the technology, are able to be there to do that, nobody will care for the monkeys. everybody will be happy for the people that can walk again.

don't get me wrong, if there's an alternative to animal testing i'm all for it. but to study and interact with something as complex as the brain, the only alternative is human testing which people dislike even more.

is it fair to those paticular monkey's? no. but it's about as fair as you and me being born in wealthy nations having more then enough wealth to even consider debating about moral issues, while <insert your large number here> africans die of starvation every day.

just the way the world works. if we'd set those monkey's free in the rainforest they'd die in fires soon thereafter as the wood is cleared for more farmland for our biofuels.

there's a time and place for everything. even utopia. it just isn't now.


RE: moral issues
By Noya on 10/17/08, Rating: 0
RE: moral issues
By Justin Case on 10/18/2008 1:25:17 PM , Rating: 2
I would rather have it done to people like you, who think prisoners are somehow less human than them.

That was sarcasm, in case you missed it.

Wanna save the poor little rat / guinea pig / monkey / whatever? Why don't you volunteer for testing?


RE: moral issues
By wvh on 10/17/2008 11:19:19 PM , Rating: 2
That was the first thing on my mind too... And I'm not squeamish either. I understand you can't make an omelet without breaking some eggs, but this does unsettle me slightly – not just because it's an animal, but especially since it's not that far away from our physique and capabilities. If I could do this to a monkey, I could probably do it to a human being.


RE: moral issues
By feraltoad on 10/18/2008 1:44:08 AM , Rating: 2
Everyone is just one sick relative away from agreeing with tests of these sorts.


RE: moral issues
By JonnyDough on 10/18/2008 3:44:45 AM , Rating: 2
Honestly, there are worse things happening we should probably be putting our attention towards. For instance, global cooling! =P ZOMG, we're all gonna diiiiiiie!


RE: moral issues
By MrPoletski on 10/19/2008 7:28:31 AM , Rating: 2
"If I could do this to a monkey, I could probably do it to a human being."

?? that's the whole idea dude, they are trying to learn how to rewire paralysed peoples nerves so they can walk etc again.


RE: moral issues
By Hardin on 10/21/2008 11:26:58 PM , Rating: 2
I would hate to be a test monkey. I still remember those poor monkeys from System Shock 2.


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