Researchers turn to VR to treat phantom limb pain

Researchers at the University of Manchester are turning to virtual reality once again, not to have another go 'round at proving whether telepathy is real or not, but to help individuals with amputated limbs recover from so-called "phantom limb pain," a sensation wherein amputees appear to feel pain in their lost limb. The treatment involves patients donning the requisite headgear and data gloves, allowing them to explore a virtual world with their missing limb restored. Patients then perform various tasks that trick the brain into thinking it can control the missing limb, something earlier studies suggested would help alleviate the often unbearable pain. While the study is definitely on the small side -- just five patients -- the researchers seem to be quite enthused with their findings, reporting that four of the subjects achieved significant reductions in pain, in one case after just a single session. Cause for further study, no doubt; let's just hope our British friends don't completely give up on their more esoteric endeavors.

[Tom @ Nov 14th 2006 10:02PM]

This is an incredible combination between technology and psychology. Phanton limb pain is an intriguing phenomenon. Past studies have shown that it is possible to "trick" the brain into thinking that the limb is actually there. Since all the pain is generated in the brain, and not by actual feeing (since the limb is gone), the pain vanishes. Previously this work has only been done with mirrored boxes. The integration of virtual reality to accomplish similar results is exciting, and will have real-world consequences for those experiencing this effect

[shaninho @ Nov 14th 2006 11:02PM]

" ... all pain is generated in the brain ... "

This is not exactly precise, since it is still a point of contention in the relevant literature. In fact there are free nerve endings and mechanoreceptors that will send somatic sensations and pain sensations to the brain, and there is an ongoing debate concerning the source of the phenomenon of phantom pain.

The two major theories concern whether or not free nerve endings from the amputated limb are sending these signals or whether it is plasticity (change) within the somatotopic organization of the somatosensory cortical areas that is giving rise to the perception of the phantom limb. (Okay some people also think that it's purely psychological, but what that really means is difficult to pin down.)

In either situation, it is well understood that there are long term changes occurring in the area of the somatosensory cortex that now is deprived of input from the amputated limb. Adjacent cortical areas are known to reutilize some or all of the somatotopic space in the cortex, but what we are probably seeing is the reverting of that reorganization back to something that was closer to the "normal" case. Jon Kaas and Tim Pons have done some nice work showing this, and there is a good paper by Florence, Jain, and Kaas (1997) showing similar cortical reorganization in monkeys.

Just goes to show that the brain is yet again proving to be amazing, and it's capable of long term change - even in adults!

[Tom @ Nov 15th 2006 12:15AM]

very true.

"Adjacent cortical areas are known to reutilize some or all of the somatotopic space in the cortex" - like how people will be able to "feel" tacticle input that occurs on one part of their body on the phantom limb, when the tactile input occurs on a corresponding cortical area adjacent to the now stimulus-deprived cortical area representing the missing limb

ah yes, neuropsychology.

[Wolfman @ Nov 15th 2006 1:10AM]

As someone with/without two legs, I find this very interesting. My phantom pain doen't last very long, but OUCH! If this works, I hope I can get connected with my X-Box.

[lectrikhed @ Nov 15th 2006 11:09AM]

Mr. shaninho

Perhaps you should review your research. There is a big difference between phantom limb pain and stump pain. You are commenting about stump pain, and the statement that some people think it is just psychological, shows your lack of expertise in the area. All pain is psychological. All pain is perceived in your head.

As for this study, I've been following it since it began. This is promising, but so far, there is no advantage over just a mirrored box. Anyways, phantom limb pain is very difficult to research, because no patient has an identical amputation. It is impossible to conduct an ideal experiment with Phantom Limb Pain. Any research, into this is important, and I applaud the researchers for attempting this.

[shaninho @ Nov 15th 2006 1:24PM]

Actual you seem to be confused, though I freely admit I am no expert on this subject. However I have reviewed quite a bit of the relevant literature.

If a free nerve ending in a stump is activated, some people have suggested (and it was quite well accepted until about 15 years ago) that the AP would travel from the the stump through the A-delta and C fibers to the brain via the spinothalamic pathway, where it would terminate in the somatosensory cortex and give a sensation of pain (yes, we are now in the brain).

This is quite different from that stimulation of the somatosensory cortex coming from intracortical stimulation (see previous post, pubmed subcortical fringe and large scale reorganization of the somatosensory cortex). Thus the debate is whether or not the afferent fibers are SUBCORTICAL or INTRACORTICAL in origin.

If you define "psychologically" to mean broadly, "happening the brain," then very little of our perception is not psychological. However in this context "psychological" means from a unique CNS origin that is not intracortical (and obviously not from the PNS).

Please find an elementary neuroscience textbook to review your basic neuroscience before flaming posts. Then read Pons 1998. And then pick up Jon Kaas from Vanderbilt. My colleagues tell me that he is quite a nice guy.

[Variblex @ Nov 15th 2006 12:55PM]

ahh why when they use virtual worlds they look something of 3d worlds on some super nes. Maybe I am just so much a gamer but if I looked at a online world like that I would laugh.

I understand there is much more complexity to making the 3d worlds most games have today, but always feel that when they use 3d environments outside of oil/gas business and video games everything looks like I am in kindergarden playing with building blocks.

Heck just hypnotize the people and turn off the pain. I have used many nlp techniques to remove pain in myself and friends. You can do taht in awake state pretty easyily.

[some person @ Nov 15th 2006 4:32PM]

i bet you that the person using that device (pic) is trying to be mario

[nima @ Nov 15th 2006 4:47PM]

I think it is interesting what they are doing with virtual reality these days. Just the other day I saw a special on CNN where they use virtual combat scenes to help our troops returning from Iraq/Afghanistan cope with their traumatic experiences rather than supress them.

[lectrikhed @ Nov 15th 2006 5:25PM]

I'm glad to see that you are an expert in 15 year old research. As for all those researchers that you are speaking about, I have read them. In fact I have read just about every paper on the Phantom Limb Pain. Also hiding behind language that non psychobiology experts do not understand does not help your case. Just so everyone else who reads what he has written is aware. His statements about multiple theories are about 15 years behind the times. He is also confusing stump pain from phantom limb pain. Anyways it's a very difficult area to study, and much of the research is conflicting, due to the nature of amputations. Phantom limb pain is due to cortical reorganization, not mechanosensory receptors. For everyone not an experiment, your brain reprograms itself to make up for the lack of input. You then get input. This virtual reality and mirrored box override that lack of input, and can thus treat phantom limb pain. If the earlier poster was correct, how would virtual reality help treat pain caused by damaged nerve endings? If that was the case virtual reality and mirrors could treat every lots of other types of pain, and it does not.

[William C. Lynch @ Dec 27th 2006 12:04PM]

My left leg was amputated in 2001. I have been in constant pain ranging from 5 to 10 on pain scale. I am on morphine sulfate and oxycodone which does not seem to help this pain but does help in my back pain and shoulder pain. The pain is so severe that I have to scream when pain hits,just a reaction I am sure,but cannot control.To your knowledge is there an treatment to give any relief even if minor. Thanks for any help,Bill.

[Peter P King @ May 18th 2007 4:32AM]

I lost my left arm in 1992 after an accident and have had PHANTOM Pain ever since.
I'm lucky to have been part of this research and been free of my pain for periods of time.
Any one who is offered Virtual Reality accept with an open mind. The more you put into it the more you will get out of it.
My hope is that something will come of the research, and those who suffer will get the opportunity to try it,.

I hope it works for them as it did for me.