Researchers Identify Phantom Limb Brain Activity

mmmscience writes "Researchers in Switzerland think they had identified the regions of the brain responsible for creating phantom limbs and the senses that go along with them. Scientists studied a stroke victim who claimed that the phantom limb of her now-paralyzed left arm could do a number of things a normal limb could do, including 'scratch an itch on her head, with an actual sense of relief.'"

Comments

But what Slashdotters really need to know...

[Anonymous Coward]

Can you masturbate with a phantom limb?

Re:But what Slashdotters really need to know...

[Hangingcurve]

If you use the left part of your brain, it feels like someone else is doing it.

Re:But what Slashdotters really need to know...

[Fumus]

"Look! No hands!"

Re:But what Slashdotters really need to know...

[Anonymous Coward]

Anything that you have physically experienced once can be replicated with enough focus and mental dedication.

For lay people, the number of times they engaged in the activity with the now absent limb should impact the ability to recreate the sensations assuming they use an entry-level, single-instance recursion method for manifestation. This method would involve identifying one remembered masturbatory experience, and then recursing on the memory - initially focusing on one aspect of sense memory (ie: olfactory, visual, etc..), and adding sense detail with each iteration.

It should be noted that persons not already suffering from socialization issues should avoid cultivating the ability to completely self-satisfy, as this can lead to all sorts of socialization issues.

Like Gil "The Arm"

[CRCulver]

In Larry Niven's Gil "The Arm" Hamilton stories (collected in Flatlander ), the protagonist lost his arm in an accident, but found that without the physical arm he had developed telekinesis with the remaining phantom hand feeling. This persisted after he got a new arm transplanted, so he had in effect three arms. Now, one can discount Niven's interest in the paranormal, peculiar for a writer usually lauded for the believable science of his stories. But I'd be interested to know if in reality the feeling of a phantom limb would persist even after a new prosthetic or even human transplant were added.

Re:Like Gil "The Arm"

[mikelieman]

Or like -- The Phantom Limb!

"He wears a lot of purple for a white guy. ..."

Re:Like Gil "The Arm"

[OG]

I'd guess no. I believe it was V.S. Ramachandran who demonstrated that he could fool the brain into getting rid of phantom limb pain by using mirrors so that the visual system interpreted the remaining limb as being the missing limb (which leads into questions about blind people and phantom limbs, for which I don't have the answer and am too lazy to look it up). If one had an appendage that looked like an arm doing the things the brain was commanding the arm to do(and possibly requiring some tactile feedback as well), the brain would probably just interpret that appendage as the missing limb instead of creating a representation as a 3d arm.

Or I could be totally wrong. Wouldn't be the first time.

Re:Like Gil "The Arm"

[Doctor Morbius]

There is no scientific evidence that supports parapsychology. All those links are nothing but pseudoscience and consist of books written by crackpots and cranks who understand nothing about the scientific method.

Re:Like Gil "The Arm"

[koiransuklaa]

I have to wonder, if there is a large body of science behind paranormal events, why don't the scientists cash in on the Randi Million Dollar challenge (or any of the several dozen smaller ones that are out there, if Randis requirements are too hard)? I can't believe that research grants in the field of paranormal studies are so easily available that the researchers just can't be bothered...

bloggers aren't jouros

[backwardMechanic]

Vacuous lack of information? What's this 'scientists in Switzerland' rubbish? We may not be the biggest country, but it would be polite to say which scientists, even where. For anyone that cares, the study was led by Asaid Khateb, a neuropsychologist at Geneva University Hospitals. Published in the Annals of Nuerology, abstract here: http://www3.interscience.wiley.com/journal/122269076/abstract

mental imagery in practice

[crescente]

It's been long suspected in sports training that mentally practicing a skill is often as useful and productive as doing the real thing. fMRI supports this: http://en.wikipedia.org/wiki/Mental_Practice_of_Action The surprising thing to me is that she actually got relief from phantom-ly scratching herself. I suspect this is some placebo effect. Or related to why you can't tickle yourself.

Re:mental imagery in practice

[bwalling]

I'm surprised by the relief from scratching as well. My dad lost part of a finger and finds that when he gets an itch that he perceives to be in the missing part, he cannot scratch it.

Could be useful

[MWoody]

Now that they've found it, I'd like to see if they could - though I understand such specific manipulation is no doubt a long way off - work on a way to stimulate the area artificially. The ability to build controllable phantom limbs could be of great use for interacting with virtual realities. Imagine, while still having full control of your senses and limbs, being able to walk around a second entirely separate world with an entirely separate body; a lucid, computer-assisted daydream, essentially.

A serious question

[Anonymous Coward]

Do male to female transexuals get phantom erections after the operation?

Re:A serious question

[Anonymous Coward]

Yes, we do.

I'm just coming up to 3 years post-op. I no-longer get a phantom penis when awake, but I sometimes have something I call "the hermaphrodite dream", where I have both a penis and vagina. The first few times, it messed with my head a bit, but now I'm kinda OK with it, and it only happens once or twice a year.

Old news. I have a better link about Phantom Limbs

[gigamonkey]

Watch this guy explain it and be amazed. The phantom Limb part comes in at around half way if I remember correctly. This was filmed in 2007 so ya old news. Vilayanur Ramachandran: A journey to the center of your mind http://www.ted.com/talks/view/id/184

for a horrifying read on phantom itching:

[circletimessquare]

consider this new yorker piece:

http://www.newyorker.com/reporting/2008/06/30/080630fa_fact_gawande?currentPage=all

basically, this poor woman's condition has bolstered neurologists rethinking of the itch sensation as something completely unrelated to pain. she had an incredibly rare "phantom itch". how disabling was it? she scratched THROUGH HER SKULL, until she was scratching brain matter

she survived, in a debilitated condition, but she did better than her roommate, who, with a similar phantom itch, scratched through to his carotid, and killed himself

read, for an especially horrifying insight into what its like to live with a phantom itch:

"But I was desperate," M. told me. She let them operate on her, slicing the supraorbital nerve above the right eye. When she woke up, a whole section of her forehead was numb--and the itching was gone. A few weeks later, however, it came back, in an even wider expanse than before. The doctors tried pain medications, more psychiatric medications, more local anesthetic. But the only thing that kept M. from tearing her skin and skull open again, the doctors found, was to put a foam football helmet on her head and bind her wrists to the bedrails at night.

She spent the next two years committed to a locked medical ward in a rehabilitation hospital--because, although she was not mentally ill, she was considered a danger to herself. Eventually, the staff worked out a solution that did not require binding her to the bedrails. Along with the football helmet, she had to wear white mitts that were secured around her wrists by surgical tape. "Every bedtime, it looked like they were dressing me up for Halloween--me and the guy next to me," she told me.

"The guy next to you?" I asked. He had had shingles on his neck, she explained, and also developed a persistent itch. "Every night, they would wrap up his hands and wrap up mine." She spoke more softly now. "But I heard he ended up dying from it, because he scratched into his carotid artery."

I met M. seven years after she'd been discharged from the rehabilitation hospital. She is forty-eight now. She lives in a three-room apartment, with a crucifix and a bust of Jesus on the wall and the low yellow light of table lamps strung with beads over their shades. Stacked in a wicker basket next to her coffee table were Rick Warren's "The Purpose Driven Life," People, and the latest issue of Neurology Now, a magazine for patients. Together, they summed up her struggles, for she is still fighting the meaninglessness, the isolation, and the physiology of her predicament.

She met me at the door in a wheelchair; the injury to her brain had left her partially paralyzed on the left side of her body. She remains estranged from her children. She has not, however, relapsed into drinking or drugs. Her H.I.V. remains under control. Although the itch on her scalp and forehead persists, she has gradually learned to protect herself. She trims her nails short. She finds ways to distract herself. If she must scratch, she tries to rub gently instead. And, if that isn't enough, she uses a soft toothbrush or a rolled-up terry cloth. "I don't use anything sharp," she said. The two years that she spent bound up in the hospital seemed to have broken the nighttime scratching. At home, she found that she didn't need to wear the helmet and gloves anymore.

Re:Randi again. . ? Oh my!

[Fantastic Lad]

So, aside from your word, which is nothing short of one big "Citation Needed", I'm going to see "1 (one) million dollars, verified in a bank account, just waiting to be had", along with a sensible set of rules that should be absolutely no problem at all for anyone having a talent of this kind, and conclude that you are either scorned because you failed it, or just incapable of understanding others might be a tad cynical of those who come with extraordinary claims.

And this is exactly how I felt about things as well until I went to explore the claims and counter-claims surrounding Randi.

Clearly, you have not done this. Why?

--That's a rhetorical "Why?" which I answered in my previous post. Citations are useful and they are out certainly available, but you are not asking for one; you are challenging with a chin-jutting attitude. What does this say about what you really want?

What do I 'win' by convincing you, other than perhaps your respect and that of society's in general? The thing is, I no longer crave society's respect (and certainly not yours) due to the work I have done in re-writing the programming in my own mind. --The combative "Jury Box" system of truth discernment is a feature of our world which has been sold to us through television with the broad suggestion that it can and should be applied in all instances including the scientific forum, but this is not the case. Here's an interesting fact: Many of the forces which exist beyond the walls of 'official culture' have to do with one's state of consciousness, and can be affected and indeed blocked through an application of intent and strong will. If you don't want to see something, then in a surprising number of cases, it is entirely possible to trick yourself into not seeing it. You can even prevent others from seeing. There are a vast number of phenomenon like this.

As for the win/lose method of knowledge distribution. . .

I've already 'won' by increasing my knowledge. Yow win nothing by fortifying ignorance. But we are taught that "Winning = Not Getting the Ego Bruised". "Being Wrong" has been attached with a powerful negative emotional cost hammered into us all through an education system which pitted children against one another through the tactic of age segregation. Age segregation makes it so that leaders are not readily found within groups, thus increasing the competition among children to very high levels while never allowing for a clear 'winner'. One result is that of, "Jocks v.s. Geeks". --The result being a shell-shocked geek community which grows into adulthood with deeply set baggage wrt losing face in any kind of contest. Thus the attaining of knowledge comes in at a distant second to being Right At All Cost. (And when I say, "Right" I do not mean, "Factually Correct". I mean "In line with the official version".) --The age segregation and the combat it forces children to undergo makes knowledge given by authority figures (like the TV) the only safe way of accumulating data because the data given is not accompanied by a sense of guilt or defeat in not previously knowing, but rather a warm-fuzzy feeling. So if you can control the media, and you also control the knowledge stream because the population will police itself, allowing no new knowledge to arise from its peers. The only thing geeks are allowed to say is simply a repetition of what TV's and various other globally recognized media authority figures have stated as being 'true'.

-FL