Wednesday, September 17, 2008

Pain and Performance

Pain and Performance
Melzack defined the Neuromatrix of pain as “pain is a multidimensional experience produced by characteristic ‘neurosignature’ patterns of nerve impulses generated by a widely distributed neural network-the ‘body-self neuromatrix’-in the brain (3).”

Anyone still there? Wow, that does sound like something right out of the movie the Matrix with big fancy words like “multidimensional” “neurosignature” “neural network” are we still talking about physiology today or in 2050? The above quote was actually from 2001, so coming up on seven years ago now, but you would be hard pressed to find a ton of acceptance to the theory
(although momentum for it gaining steam).

But how does this relate to me? I just want to perform at a higher level?
A brief tangent about pain

The old school view of pain was that when you stuff that hot cream cheese puff from the Chin Young buffet in your cake hole, the signal travels from your tongue into the pain center in your brain. The hunt was on as scientist spent years trying to find this elusive, Bigfoot like creature in the brain. Let’s try the cortex, maybe that is it? Nope. Thalamus? Not it again (10). On the search went, but to no avail (9). The thought was that once we find the pain center, we can cut it out, ablate it, drug it and bammmm-o, no more pain. While this fantasy sounds awesome, it is just that---a fantasy as physiology is not quite that simple. We now know that there is no pain center. Drat, so much for the trying the easy stuff first. We know that pain does live in the brain, but it is multidimensial (there is that word again); most likely stored away in the nooks and crinkles just like a squirrel hiding nuts for the winter in your lawn.

Pain is produced when the brain perceives that danger to body tissues exists and that action is required as a survival response. Back to our friend at the buffet with the hot cheese puff in his mouth. What happens next? He either tries to dump the said cheese puff on to the plate in a very non conspicuous way (can you give me a “good luck buddy” shout), or add some cold water perhaps. Either way, it is highly unlikely he will sit there as it smolders into his tongue and pollutes the room with the smell of burning flesh. Pain is an action signal-do something!
The brain and the nervous system control ALL muscle movements. When pain occurs it inhibits the nervous system as a protective mechanism. Remember that the body only cares about survival and does not give a hairy rat’s butt about performance. If I injure my elbow, my nervous system will start to shut down the muscles around that joint as a protective mechanism to try to prevent further damage (ala arthrokinetic reflex).

The Neurosignature
Pain is a specific interpretation of the brain, or as Melzack calls it a “neurosignature” (no that is not how Neo from the Matrix signs his name, that would be the neosignature). This neurosignature is dependent on many imputs (multidimensional). The main inputs into the brain are proprioceptive, visual, and vestibular. Remember that proprioception is the body’s 3D map of itself and allows you (ok your friend) to touch their nose with their eyes closed when they get pulled over by the Smokey along the road. Everyone is familiar with vision, as we are highly visual creatures (some would argue males more so than females, but I won’t go there). Vestibular refers to the function of the inner ear and balance. With every step we take (yes even with every breath you take for all you Police fans), the brain is receiving inputs from each of these systems and combines them to form a neurosignature. I hear some academics in the back shouting “where is the data” so here you go.

Phantom Limb Pain
Many times those who have lost a limb, will complain of pain coming from their lost limb! At first blush, the thought “they must be insane” runs through my head, but several studies have shown this to be true in very sane people; and the pain is real (5). How can this happen? So the very same inputs that provide the brain with signals interpreted as pain, can run amok in the brain and actually produce pain!(4) So it is not just a one way system, as the brain it seems can produce pain that feels like it was coming from the lost limb-kind of like working for a double agent. Imagine you are a super top secret agent (inputs from the body) hired by Emilio the Shark (the brain) to get info on those sneaky Russians (lost limb). Yeah those Russians are sneaky, so watch out Pavel, But you then learn that Emilio the Shark has sold you out and is just creating information for the Russians! Dang it. So the brain appears to create pain from the lost limb.

The pain can many times be induced by a conflict between visual feedback and proprioceptive representations of the amputated limb (8). If this is true, it should be fixed by reversing this and presenting a “working limb” to the brain, right? By using a mirror box, you can create an image (from the good limb) to appear where the lost limb would normally be in space. This can “trick” the brain into believing there is a limb there, and many times the pain will diminish (1).

Placebo Effect
Everyone has heard of the placebo effect by now. While there are many different flavors of it, it is believed that the brain (and perhaps the spinal cord) play a key role! Obvious I know. Pain depends on both biological and psychological factors (2). Matre et al. (2) did an experiment where they heated up a small patch of skin on volunteers (always read the fine print) and the only difference was that one group was told that this special magnet (which was not even a magnet, just a lump of iron to look like a magnet) would reduce the pain. Sure as heck, it did just as predicted with the placebo group reporting less pain! Other studies have shown similar results (6), and it is common place to include a placebo group in almost any experiment.

Seriously man, how does ANY of this help me?
Ok, so we know that changing the inputs to the brain via proprioception, visual, and even vestibular inputs can alter the perception of pain. Even the context of the event (placebo effect) can even alter it (7). So how goes this help you increase performance?

Pain and Performance
Pain becomes a huge priority in the body and if you are not sure, then ask anyone in pain! Remember that we are a survival based organism and while pain works great to keep us alive at certain times, if you are dealing with pain you will not have peak performance. Still don’t believe me? Go out and run your fastest 100 meters. Now have Emilio the Shark kick you square in the nut sack and try it again. I can guarantee your second performance will not be as stellar.
Just as in the mirror box example, we can alter the brain’s perception of pain via proprioceptive, visual, and vestibular input! Injury is a big event and it carries a pretty hefty neurosignature. I worked with a client that had sprained his left ankle pretty bad at a fun house and we used these principals. As he was walking through the fun house, minding his own business, a super scary dude jumped out at him as he turned his head to catch a glance of him. Unfortunately at the same time, he stepped wrong with his left foot and rolled his ankle. So I set out to use some Z Health “voodoo” on him. Actually Z Health is a system based on the principals discussed here for altering the inputs into the brain to reduce pain and increase performance (Z Health in MN ); so I need to credit Dr. Cobb the creator of Z Health for all of his efforts.

Back to our fun house friend and I had him do a specific Z Health joint mobility drill to increase the proprioceptive input (this was a wrist up and down motion), with his eyes up and to the right (visual input) and in his case also with his head rotated to the right and up (vestibular input); and within a few motions we were able to get his pain from a 6/7 on a 1-10 scale to less than a 1. I was in essence recreating this event for his brain, but in a safe environment this time (I left my clown suit in the closet). Another way to explain it is that we just gave the brain the correct inputs to alter its perception of pain. Amazing.

Conclusion (aka read this part for sure)
In conclusion, from our good buddy Melzack (who also had help from Patrick Wall) defined the Neuromatrix of pain as “pain is a multidimensional experience produced by characteristic ‘neurosignature’ patterns of nerve impulses generated by a widely distributed neural network-the ‘body-self neuromatrix’-in the brain (3).” Definitely a mouth of futuristic Matrix-like words, but we know that pain lives in the brain and it can be modified by changing proprioceptive, visual, and vestibular inputs. Decreasing pain will have you on the fast track to enhanced performance!

1. Chan BL, R Witt, AP Charrow, et al. Mirror therapy for phantom limb pain. N Engl J Med. . 2007; 357(21):2206-7.
2. Matre D, KL Casey, S Knardahl. Placebo-induced changes in spinal cord pain processing. J Neurosci. . 2006; 26(2):559-63.
3. Melzack R. Pain and the neuromatrix in the brain. J Dent Educ. . 2001; 65(12):1378-82.
4. Melzack R. From the gate to the neuromatrix. Pain. . 1999; Suppl 6:S121-6.
5. Melzack R. Labat lecture. Phantom limbs. Reg Anesth. . 1989; 14(5):208-11.
6. Oken BS. Placebo effects: clinical aspects and neurobiology. Brain. . 2008.
7. Quevedo AS, RC Coghill. Attentional modulation of spatial integration of pain: evidence for dynamic spatial tuning. J Neurosci. . 2007; 27(43):11635-40.
8. Ramachandran VS, D Rogers-Ramachandran. Synaesthesia in phantom limbs induced with mirrors. Proc Biol Sci. . 1996; 263(1369):377-86.
9. Shaw KA, VK Srikanth, JL Fryer, L Blizzard, T Dwyer, AJ Venn. Dual energy X-ray absorptiometry body composition and aging in a population-based older cohort. Int J Obes (Lond). . 2007; 31(2):279-84.
10. Spiegel EA, HT Wycis. Present status of stereoencephalotomies for pain relief. Confin Neurol. . 1966; 27(1):7-17.