Kung Fu Physics anyone ?

Tim's Discussion Board: Concepts : Kung Fu Physics anyone ?
   By tobias (Unregistered Guest) on Friday, September 16, 2005 - 09:37 am: Edit Post

www.kungfuscience.org/access.asp


   By robert on Friday, September 16, 2005 - 12:50 pm: Edit Post

very interesting, there is alot of truth in this link, unfortunately, its the weekend and i refuse t read(well close enough to it):-) jk, another interesting scientific approach to martial arts is the biological psychological one, did you know that the spinal cord has motor reflexes wired into it as well? for example, when you feel something hot, and pull your hand away, well, these arent neural transmissions from your brain, but from your spinal cord, in other words, you dont have to think in order to produce a reaction ... kinda rouses wonder about internal martial arts... is this spinal reaction honed in any way?


   By Jerry (Unregistered Guest) on Tuesday, February 28, 2006 - 12:24 am: Edit Post

Topic is Kung Fu Physics, but it's really Gong Fu Neuroscience at this point. I have to recap some basic neuroscience concepts to answer this question.

Yes, of course, there are reflexes at the spinal level. In fact the only two places you have reflexes are spine and brainstem. Spinal reflexes mainly involve trunk and limbs; brainstem reflexes involve cranial nerves, muscles of the head, special sensory organs like eyes and ears, and the autonomic nervous system (glands and internal organs).

The spinal cord is not really distinct from the brainstem; there's no distinct boundary. Where it comes out of the skull, which is also where fibers cross over from right to left and vice versa, that's where we draw the distinction, but it's pretty arbitrary.

The spinal cord is NOT just a telephone wire carrying messages between the brain and the body; it would really be more accurate to consider it part of the brain. In humans, motor activity is more cephalized, i.e., moved up into the higher brain, so a decerebrate human can't walk, but even higher animals like horses can walk, or at least make walking movements, with the brain disconnected from the cord.

By the way, there is little or no learning taking place in the cord or brainstem; learning is basically cortical.

So is there any effect of learning (in internal arts, external arts, or any other activities) on reflexes? Sure. "Afferent" means "carrying (messages) to (the brain)"; "efferent" means carrying away.
Sensory impulses are afferent, going from the body to the brain, efferent is mostly motor, messages from the brain to muscles (glands too).
There is also something called the "efferent control system" that allows the cerebrum to exert some control over spinal reflexes, for example by changing the set points of stretch reflexes.
Flexibility training is mainly about adjusting the set points of stretch reflexes.

Before getting back into martial arts, I spent a couple of years studying music, mostly hand drums. When you to learn to play the Middle Eastern doumbek, you have to learn to hit the drum with nearly the weakest finger you have, the ring finger of left hand, using a rotary motion of the forearm. It's very difficult at first; I spent a few weeks getting good at it, and when I had mastered it I realized it wasn't about developing strength or flexibility in the hand or arm; it was coordination. What you have to learn is to relax all the muscles in the arm except the one, or few, that produce that movement, otherwise it doesn't work. It's much the same with "relaxed whole body power" in ima, except more complex.

I guess you could say that motor learning is mostly, or at least in large part, about adjusting various reflexes so they don't interfere with each other (or with voluntary movements), or so that they work together at the right time.


   By Chad Eisner on Wednesday, March 08, 2006 - 10:29 am: Edit Post

Interesting post.

a question: How is the learning of motorskills related/affected by the neuroplasicity of the brain? Do the same priciples apply or is there a seperate mechanism that adjusts the autonomic responses during movement?

Also, wouldn't the strectching priciple of reseting the myotatic be indirectly (rather than directly) causeing the points to change? Like in PNF, your consious brain at least, is focusing on the contraction and the relaxation rather than the direct process of resetting the myotatic thresholds. I'm just wondering to what extent stetching is cortical.


   By Jerry (Unregistered Guest) on Wednesday, March 08, 2006 - 11:16 am: Edit Post

Chad,

I don't really understand your question. "Plasticity" could be interpreted such that plasticity IS learning, but usually it refers to the ability of the brain to reorganize after a major injury, which is much greater in children than adults (but still not unlimited).

I'm not sure what you mean by "autonomic responses during movement". You can walk down the street cheerfully whistling, in a parasympathetic-dominated state, i.e. calm and relaxed, or you can be all tensed up with your stomach churning. If you encounter a threat, of course you'll likely go into a sympathetic-dominated fight or flight mode.
Autonomic activity affects glands and smooth muscle as well as skeletal muscle, so your stomach may tense up or churn, your bowels may turn to water, skin flush, etc., as well as increasing the level of tension in skeletal muscles.

For whatever it's worth, Kumar Frantzis claims that the main idea in internal styles is to maintain a relaxed, calm, paraysmpathetic-dominated state while you're pounding your antagonists to pulp!
(As opposed to being in an "animalistic" rage while you beat them up).

On your second paragraph, I think the thing to keep in mind is that "cortical" doesn't mean "conscious". Also, "cerebral" doesn't mean cortical. You have no conscious awareness, for example, of how your visual cortex sees images.
If you want to talk about the central nervous system being hierarchially organized from low level to high, between the lower levels of spinal cord and brain, and the highest level of cerebral cortex, are more levels of subcortical structures in the cerebrum.

I'm not expert on these questions, but if you can formulate the questions more clearly I can try to find out; I have access to medical literature and to a lot of neurologists and neurosurgeons.
Maybe write me off the board and we can report back if we come up with anything interesting.

Anyway, I was NOT saying that you could change your flexibility just by thinking about it! If I could do that, I'd have all kinds of miraculous powers. The conscious mind is thinking about whatever it's thinking about. If it's smart enough to identify the best exercises to do, that will be very helpful, but it's doing the exercises that makes the difference.


   By Jason M. Struck on Wednesday, March 08, 2006 - 11:22 am: Edit Post

i don't think the positive gains in ROM from PNF are at all cortical. They are pretty much reflexive. GTO/corpuscle/neurological inhibitions that are not under conscious control. That's part f why it works so weel when conscious efforts are plateauing.

plasticity: the tendency to be changeable. (malleable)
by the way, i don't think real motor learning is ever 'autonomic'. Greater efficiency in consciously learned movements comes through greater refinement of the nervous system (myelin sheath development etc). Potentiation. Impulse takes a course, it's more likely to take that course again. Pefect practice makes perfect, and there's bio-neuro proof.

plasticity: the tendency or capacity to adapt or change.


   By Jerry (Unregistered Guest) on Sunday, March 12, 2006 - 10:16 am: Edit Post

Jason, I don't know if we're going to get anywhere with this discussion because there is so much terminology that we're not all on the same page with. I don't know what PNF is, or GTO, or what you could possibly mean by "corpuscle" in this context.

"Autonomic" threw me off; it usually refers to the autonomic nervous system, glands, organs, smooth muscle. It doesn't mean "automatic".

I did get some advice and feedback, and naturally, the experts disagree about whether there is learning at the spinal level.
However, there is some plasticity in the cord, i.e. the ability to reorganize after some kinds of injury, so who knows, there might be some learning. Further research. Certainly there has to be learning in the cerebellum and in some subcortical structures, not only in cerebral cortex.

btw do you have a reference on the myelinization thing?

I think there are two important points here.
One, to make a voluntary movement, especially a complex one, many systems are involved: motor cortex, basal ganglia, cerebellum, spinal cord, sensory input, etc. There are spinal reflexes, to be sure, but by themselves they result in simple movements only. However, they are also an essential part of complex voluntary movements, which won't work without them.
In humans, motor control is highly encephalized, that is, higher brain centers are much more involved. That's why we can't run around without a head like a chicken, and why chickens can't learn gung fu. Even horses don't have to learn how to walk, but we do. That makes the child helpless for the first few years, but allows much greater versatility of motor skills in the long run.
So bottom line, complex movements require activity from all levels of the nervous system.

Secondly, there is a progression in motor learning. At the beginning, whether it's executing a martial arts technique, tying your shoelaces, or operating a manual transmission, your conscious mind has to be fully involved and even then you can't do it very well. Eventually, with practice, it gets so automatic that you can do it and perhaps not even be aware of it, as in shifting the gears in your car or tying your shoelaces. The less conscious attention is required for executing movements correctly, the more is available to pay attention to other things.


   By Chad Eisner on Sunday, March 19, 2006 - 01:38 pm: Edit Post

Jerry,

I may be getting my concepts from different fields so our terminology may not match up.

What I mean by the first question is this: Is the process of cortical (taking place in the neo-cortex, or even the brain in general) learning ralated to the process of nueroplacitiy (either definition can be applied I guess). When the brain is injured and reorganizes it's various pathways, patterns to accomidate the damaged or missing pieces, that process has been likened by some to the process of learning in the general sense more more so in the working out complex movements, any skill that involves physical and mental engagment (Sports where one must be using technique and strategizing at the same time), or the breaking of bad habits (like uncounsious "ticks" or behaviors). I think what this camp ios doing is saying that the process of learning certain things requires the brains ability to re-organize in order to intergrate what ever is being learned. I was simply asking your opinion on this point.

The second thing I was trying to say was, the resetting of the reflexs (I used "autonomic" because I am accustomed to that word. I appologize for any misuse or confucion) seems to me to be an indirect process. You kind of answered this already by saying that you cant change these things by thinking about them. I was responding to this:

"There is also something called the "efferent control system" that allows the cerebrum to exert some control over spinal reflexes, for example by changing the set points of stretch reflexes.
Flexibility training is mainly about adjusting the set points of stretch reflexes. "

The way you describe it sounds like the brain it'sself changes those set points (Wether consious or unconsious). PNF (proprioceptive Neuromuscular Facillitation) Or contract relax stretching is , as has been explained to me, an indirect method that does not involve the brain at the "reflex" level. The brain is focused on the contraction and the movement immediately following it, the flexability is increase by the spinal cord resetting the myotactic "set points". the way I understand it, those set points are changed because of the various connections, and the change is largly physiological. You have already stated that you don't believe one can increase flexability by thinkikng about it so as far as I am concerned you answered my question. If you have anything to add, please do.


   By Jerry (Unregistered Guest) on Tuesday, March 21, 2006 - 09:31 pm: Edit Post

OK, Chad,

sorry, I should have remembered what PNF was, but I've just always thought that was a ridiculous term, too long and pretentious, when you can call the same thing by a more reasonable term like "isometric stretching". So I kind of forgot about that term as fast as I could every time I ever learned it, and stuck with "isometric stretching".

I can't at the moment offer a coherent explanation of why PNF works, but it certainly isn't that the brain is too busy with the contraction and the cord is left on its own!
Pavel Tsatsouline has a really good simple explanation, but I just moved and I can't find the right book. I'll try to come up with a better explanation later, but for right now,
suffice to say that isometric stretching tricks the nervous system into not applying a stretch reflex when it otherwise would.

VERY briefly, a stretch reflex works like this:
your central nervous system (brain + spinal cord) knows where your joints are in relative position by means of sensory cells in the tendons called Golgi tendon organs, and it knows how much a muscle is contracted from other sensory cells called muscle spindles. To perform a movement accurately, it has to take this information into account. When the information from these organs is that a joint is being stretched "too far" (according to established parameters, that is, what you've trained yourself to by your activities or lack thereof), the muscles contract to stop the joint from being injured. Muscle spindles are involved in the process of contraction; it's how your nervous system knows when it's contracted the muscle enough.

The strong isometric contraction maxes out the muscle spindles and they're unable to mount a stretch reflex, so you're able to stretch further. Something like that! So maybe you could argue that where it's really working is not even at the spinal cord level, but in the muscles themselves. However, the change, or re-organization, or learning, that takes place is in the central nervous system.

Sorry I can't explain better; my own understanding needs improvement. I'll see what I can do later, but anyway, no, it's NOT that the BRAIN is maxed out and the spine is left unsupervised!

Yes, I would say that the resetting of set points for stretch reflexes occurs mainly in the brain, not exclusively in the spinal cord. The changes that take place are probably in multiple locations, but certainly not just in the cord.

Patients under general anesthesia have absolutely no stretch reflexes at all; you have to move them very carefully, because their joints have no protection from stretch reflexes. You can bend them all over the place like taffy, then when they wake up they are as stiff as ever. The point of this observation is that the spinal cord is still working under anesthesia; it's the suppression of brain function that causes the loss of stretch reflexes during anesthesia. The limitations on movement in the awake person are a product of the function of the whole nervous system, including the brain.

I would say, sure, plasticity and learning are closely related. For example, if you learn to play an instrument like the violin, the cortex for the left hand (which is on the right side of the brain) gets bigger than the cortex for the other hand, because there's much more to controlling the left hand fingering than there is to the bowing, which is done with the right hand.
So yes, at least some learning, and specifically some learning of complex motor skills, which is what we're talking about, requires plasticity.

Where that physical re-organization takes place is another issue. The classical view is that learning does not take place in the spinal cord or brainstem, only in the cerebrum. However, there is some plasticity in the spinal cord, so who knows, maybe re-organization of the cord IS required for some motor learning. The main point, I think, is that complex motor skills require input from many nervous structures, including basal ganglia, cerebellum, cerebral cortex, and sensory organs, not just the spinal cord.

Coma patients, or brain-dead patients, sometimes exhibit very simple or disorganized movements: spastic twitches, cerebrate and decerebrate posturing (one is flexion, one is extension, but both are very limited), or withdrawal from painful stimului. However, human patients don't run around like a decapitated chicken, and they don't perform complex learned movements such as walking, playing instruments, or gong fu forms.
They have to wake up first before they can display those skills.


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