19 February 2009

Shintaido from the physiological perspective, part 1: reflex arcs and natural movement


Excerpt of an interview with Ula Chambers, 22nd July 2003

Ula Chambers is a senior instructor of Shintaido in Great Britain and a professional physiotherapist. (At the time of this interview, she was in her final year of study as a physiotherapy student).

Reflex arc, defined: The route followed by nerve impulses in the production of a reflex act, from the peripheral receptor organ through the afferent nerve to the central nervous system synapse and then through the efferent nerve to the effector organ.

If this is too technical for you, don't be alarmed. In more day-to-day language, a reflex arc occurs when a sensory impulse travels to the central nervous system and back out to the periphery (say a muscle), and there is a response before the person makes a conscious decision to respond.

Ula Chambers: Balance is really interesting, becuase there's a kind of chain of balance reactions that happen. It involves the core stability muscles in your trunk, but there's also a foot/ankle reaction. For instance if I'm falling over there, I don't have to think "I'm going to put my foot there to stop myself from falling over." Eventually you realize that you have put your foot there.

David Franklin: You're saying that when you loose your balance, it just happens-- the foot goes by virtue of this sensory nervous system reflex arc.

UC: Yes, and it involves various muscles in the body. The muscles that need to do it work, but also all the muscles in the torso have to respond to stabilize the trunk. For instance, if I were standing here and somebody brushed past me, what happens is it begins with an ankle reaction to stabilize the feet on the floor. It's a tightening of the gastrocs and tibialis at the front which stabilizes the leg at the bottom.

DF: Suppose I were to say that when we do wakame taiso ("seaweed exercise" わかめ体操), we are invoking this reflex arc that normally operates automatically and unconsciously. And now we are trying to do it consciously. We're trying to activate it consciously, but we're not trying to do each movement consciously. Is this perhaps one of the things it means when we refer to "natural movement" in Shintaido?

Let me put it as a speculative question: what might the effect be of taking this reflex arc that exists already as a pattern in the body, and trying to be conscious of it, without interfering?

UC: If you're conscious of it, then it becomes a process of your higher brain functions. When it's unconscious you don't have any knowledge of it as such. But when you have knowledge of it, then it's part of a wide range of choices that you have for voluntary movement. So therefore it's a tool, and you can use it. You can choose to use it, as opposed to it just being there for a particular instance. You can make the decision to work on it.

If we do wakame for instance, and we train ourselves almost to feel how it is to be unbalanced, depending on how flexible you are or how much you can let go, the effect is to challenge the system. It's like the study we do with bokuto (wooden sword 木刀), where you're understanding what's going on behind you, developing your sixth sense. I think you're training your senses to be aware of things, and then to be able to use them. It's like that whole thing with the Star Wars Jedi stuff, "use the force," it's that kind of thing we're doing.

DF: Part of what I'm hearing is that we often make this vague statement that Shintaido will help you to develop more natural movement, and if someone were to ask you "Well what does that mean, specifically?" this would be one of the answers: we take these reflex patterns that are part of the human body, and develop them, and use them more consciously. Which leads me to another question:

What kinds of things might interfere with reflex arcs of the sensory nervous system?

UC: You have inhibition and excitation from the higher centers. For instance, you know about the knee jerk reflex, when the doctor hits the knee with a little rubber mallet. Well, if they're thinking about it, sometimes you do that to people and it's practically nothing. That's because they're aware of it, they've stopped it somehow; there's some kind of inhibition going on from the brain that says "I'm not doing this." So you have to distract people, tell them to count in French backwards from 10, or spell their mother's maiden name or something, and then you do get a response.

DF: So to clarify, reflex arcs can be inhibited or enhanced, depending on what the conscious brain is doing.

UC: Yes. What it does is, the brain will adapt the reflex to suit the environment. So what we're doing is we're creating an environment.

DF: Would you say that we're creating an environment that nurtures that reflex to occur more?

UC: I suppose so, because we're making it happen often. But we're making it happen in such a way that we're controlling it.

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