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Old Forum A clarification on "reflexive stability"

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Zach,

If you read carefully, they are not really modifying the reflex pathway. They are asking people to consciously override the reflex. This is an example of a learned motor response. In this case, the purpose of the learned motor response is to suppress the reflex. The reflex itself is not being modified. This would be like teaching a person to quickly cover a light when it comes on. You are changing what the light is doing – only the response to its coming on.
 
Matt,

You say:

"Perhaps some of the confusion comes from treating all reflexes as reactive (to some stimulus) and not anticipatory.  The mind can anticipate a movement and then the nervous system reacts to that in anticipation.  I’m no expert in the physiology, just philosophising."

A reflex is reactive by definition and requires a stimulus – always, no exceptions. There is no way to get around this. If the mind is anticipating something, this now in the realm of some very complicated integration and can no longer be called a reflex.
 
Scientist

Going for a Russian split would fire the stretch reflex for the majority of the people. But when stretching you reprogram the nervous system to let the reflex kick in later. When a person on the other hand lives a sedentary lifestyle, which leads to a strength loss, the stretch reflex will become more sensitive.

Don't you interpret these examples as a change of ones reflexes?
 
I need to bang in here...  all Scientist is saying is that if "reflexive tension" does not occur as a reflex arc, below the brain, then let's not call it a reflex, regardless of how many peer-reviewed studies do.  Mixing terms leads to confusion.  So, is it a reflex arc?  It might be.

Does anyone know about "actual" reflexes, their dysfunction, and subsequent rehabilitation, if any such cases exist?  It might shed light on how "reflexive tension" responds to certain exercise.  My suspicion is that "reflexive tension" is improved through training, because it is degradable... like, use it or lose it.  This may be why only certain few practices improve "reflexive tension", and not just movement in general.  This may be suggesting that a reflex arc is involved... or not.

The knee-jerk reflex is stimulated when the patella tendon is rapidly shortened.  No brain interaction.  The rotator cuff muscles are fired when the arm is used.  No brain interaction.  Or is it, just no conscious brain interaction?  This is a crucial distinction.  And what Scientist is asking.

I think it's worth exploring.
 
Scientist-

You remind me of another individual that posted on this forum that enjoyed being a contrarian.   Perhaps you picked a new pseudo-name to engage in online debates.  Brett provided you with great info and you're hung up on a word rather than the concept and most importantly how to apply it.

Here's a drill from Mark Snow, I shot this video in a hurry for my students so you'll have a field day picking apart the terminology I use, enjoy!  More importantly, do the supine squat I show at 2:50 using a band below the lumbar spine, the quaking and tension you feel trying to keep the back in place while consciously engaging the movement is beyond your conscious control, your intent is pushing the lower back in the ground and straightening the legs, the pelvic floor firing is what RS is, call it whatever you like:

https://www.youtube.com/watch?v=MyccMnMSlrA&feature=youtu.be
 
Henric,

I would say that your brain is learning to ignore or override the reflex, not change the reflex itself. I realize that we are very finely mincing words at this point. It probably is not a big deal at this level.

 

Al,

I agree with for the most part. A few thoughts:

"...regardless of how many peer-reviewed studies do." I don't agree that they are using the term in that way. There is some confusion in reading these statements being quoted.

 

"My suspicion is that “reflexive tension” is improved through training, because it is degradable… like, use it or lose it."

Strength is simply the ability to produce tension. So aren't we just training strength for the existing reflex arc to make use of?

"The rotator cuff muscles are fired when the arm is used.  No brain interaction.  Or is it, just no conscious brain interaction?  This is a crucial distinction.  And what Scientist is asking."

The brain plays a large role in rotator cuff activity. When the learned motor program "throw ball" is engaged, a specific pattern of motor activity to these muscles is begun. During the actual moment itself is when things get fine-tuned by reflex pathways that take in information from sensory structures within those muscles (like the muscle spindle). So the interaction of both kinds of activity are crucial for function.

Zach,

This is the only name I have ever posted with. You are right in that what I am saying likely has little if any effect on actual training. It is entirely academic. However, I am an academic and spend most of my time teaching human physiology to college students that are aspiring medical professionals, so I think that accurate terminology is important. I think this matters most because medical professionals have a lot to learn from this crowd, but things will not go smoothly if they think you don't know your stuff (which, again, does not in any way mean you don't know how to effectively train people).

 
 
1. It would be worth sorting out which reflexes are automatic and which are not.  Standing on one leg or getting in a quadruped position does not guarantee hip stability.  It might.

2. A reflex is a response to some activity.  Reflex cannot be trained because it "just happens", but activities that bring about reflexes can and should be trained and will improve reflexes.

3. "The brain plays a large role in rotator cuff activity. When the learned motor program “throw ball” is engaged, a specific pattern of motor activity to these muscles is begun. During the actual moment itself is when things get fine-tuned by reflex pathways that take in information from sensory structures within those muscles (like the muscle spindle). So the interaction of both kinds of activity are crucial for function."  THIS.  Movement improves and is interconnected to stability i.m.e.  Never heard this example before.
 
Scientist,

I agree entirely that terminology is important and am not belittling the need on everyone’s part, myself included, to refine the science of training and movement so that all trained in it are speaking the same language.

“Strength is simply the ability to produce tension. So aren’t we just training strength for the existing reflex arc to make use of?”

-correct me if I’m wrong but isn’t this a somatic reflex arc you’re describing? If so then no, this is not strength training at all. We are not engaged in increasing tension while scratching, withdrawing, etc.

-you seem to differentiate between this and motor learning a few posts before asking this question, please clarify.



“So is the learned motor program conscious or subconscious? I would say that it is initiated consciously, but the program then runs its course subconsciously for the most part.”

-I agree 100%, so by this perspective if we use the definition of reflexive:

”happening or done without thinking as a reaction to something”

then the firing and timing seen in stabilization muscles is occurring as a reaction to the conscious initiation of a particular movement pattern.
 
Sean

I'm not entirely sure how to define "automatic" in a  physiological setting.

Zach,

"correct me if I’m wrong but isn’t this a somatic reflex arc you’re describing? If so then no, this is not strength training at all. We are not engaged in increasing tension while scratching, withdrawing, etc."

What I am saying is that strength training gives the reflex more strength to activate when needed. nd obviously, nobody is trying to train their withdrawal reflex.

”happening or done without thinking as a reaction to something”

This is a definition based on the inaccurate misuse of the term that has become common, and it is where most of the confusion is coming from. The definition above is not a technical definition of a reflex, it is a use by the general population that is non-technical and not very descriptive. It is a bit like someone using "correlation" when they really should use "association", or "theory" when they really should use "hypothesis". What I am arguing for is using technical terminology that describes physiology accurately, and avoiding common usage that is not very descriptive or accurate.

 
 
Hi Scientist,

Thanks for your replies and I can see how my use of terminology hasn't conveyed my idea accurately - I understand precisely what you're saying (a reflex is a reflex, and a direct response to stimulus).  It is the usage of reflex in reflexive stability which is technically questionable, but as Zach said, it conveys the idea, rightly or wrongly.

What I was thinking of in being anticipatory - I would imagine that the body is not reacting to a direct (say touch) stimulus when walking.  The fluid motion of any movement would have to act as a "whole being greater than the sum of the parts" concept in my opinion.  Like Brett said way back, (paraphrasing) - well to me (philosophically) it seems the stabilisers have done their job before you have the physical stimulus to initiate a response from the muscles.  This has to do with the timing of the sequence involved giving a movement which is greater than the part-by-part analysis of the action-reaction by the muscles.

If the timing is off too - you'd have a delayed effect - a sluggish response as your muscles are still acting on a previous stimulus.  If it is not anticipating, you'd be also jerky.  The fluidity seems to come from a pre-emptive response - maybe you'd classify all of that as a motor pattern.  I agree - it is not a reflex in the technical definition, and physiological activity of the body.

A further case in point - what or how would you define the following... (sorry for this short contextual intro - I have a job that can have moments of high stress (like this morning, which is why I couldn't participate here in real-time)).

Now my mind is anticipating various events, none of which are actually physically happening.  Yet my body is physically reacting to this - my nervous system reacting to a perceived threat.  I could control this, but the reaction is there with no direct physical stimulus to my nerves.  These reactions of my body to the stress would involve various reflexes in the technical definition, most subconsciously controlled - with the "cause" being my mind, my belief, my anticipation of an event - which didn't happen as I expected for a start - and the reaction to the anticipated event is much more comprehensive than the actual event which happens (which would be me reading something - my eye being stimulated and that initiating a motor pattern).

Anyway - I just have another idea...will have to research...
 
Scientist-

Now that we have determined your objection what term would you nominate to convey "reflexive stability" using technical terminology?  Be careful, if it's really good I will steal it.
 
Matt,

I'll copy what I wrote in a previous post. I think it addresses what you are bringing up – mainly that you consciously initiate a movement, but information from reflexes and other sensory inputs modulate that movement once it has begun:

"The brain plays a large role in rotator cuff activity. When the learned motor program “throw ball” is engaged, a specific pattern of motor activity to these muscles is begun. During the actual moment itself is when things get fine-tuned by reflex pathways that take in information from sensory structures within those muscles (like the muscle spindle). So the interaction of both kinds of activity are crucial for function."
 
Just quickly - reflexive can have a meaning grammatically and philosophically.

Philosophically it conveys the idea that a relation (binary) of an object being related to itself.

Perhaps it was this idea which was considered - yet I am still to see exactly how.  But just to put it out there - will ponder.
 
Zach,

To me, "proprioceptive stability" makes much more sense. Proprioceptors detect changes in muscle and joint positioning, and share that information both with reflex arcs (the truly reflexive part of this), and also to the brain (e.x. spinocerebellar tract – this is the non-reflexive part of the equation). That term would combine both components involved. The downside (or maybe upside if you like teaching people new things) is that the vast majority of people are unfamiliar with the term proprioception.

 
 
Actually I was thinking of something more than that but anyway, thanks nevertheless.
 
Just to add to my earlier thought - I can see how it may be true - the muscle is acting "on itself" to provide stability therefore reflexive.

Brett perhaps will be able to comment on the accuracy of that, understanding the action of these stabilisers.
 
Now wait just a damn minute here.  It was my idea to talk about reflexive stabilty.  Everyone needs to go down to my thread to talk about this.
 
A timely podcast from Gray Cook today, discussing a definition of strength.....and stability.....

"If we kill stability and replace it with motor control, and we kill strength and replace it with work capacity, then hopefully no one will be offended. "

Full thing here, not sure if it is available to non subscribers.

http://functionalmovement.com/articles/Podcasts/2014-12-17_strength_defined

 
 
Matt, you are simply off-track... you are trying to tag a new definition on to an already established term.  Scientist lives in a world where every term needs to have one reference to reality, and one distinct reference only.  If reflex describes more than one phenomenon, than it is useless as a description, and requires more words to allow a hearer to understand a speaker's meaning.  This distinction of terms makes for more accurate communication.

So, Scientist said:
The problem that I have with this is that reflexes are clearly defined phenomena.
and,
The thing about a reflex arc is that it is set. It cannot be modified or changed. It also is characterized by the stimulus always producing the exact same response. When a physician taps your patellar tendon and your quadriceps contracts, this is simply because the tapping stretched the tendon, which stretched the muscle. The circuit for the stretch reflex is wired so that when the muscle stretches (like it does when you being to lose balance and fall), the response is to contract (so you stand back up).
When he might have said something like:
A reflex arc is a neural pathway that controls an action reflex. In higher animals, most sensory neurons do not pass directly into the brain, but synapse in the spinal cord. This characteristic allows reflex actions to occur relatively quickly by activating spinal motor neurons without the delay of routing signals through the brain, although the brain will receive sensory input while the reflex action occurs.
So, a reflex occurs without brain interference.

Now, we are using the term, "reflexive tension" to describe the phenomenon of how muscles fire in sequence to stabilize the structure.  This phenomenon includes the actions of both reflexes, as defined, and brain interaction (whether unconscious or conscious).  So, "reflexive" is not an accurate descriptive term as it includes brain action.  Reflex can't mean both, "without brain" and,"with brain" at the same time.

This is all that is being said... we agree that the phenomenon does exist, that it is trainable, and that it seems to improve the quality and authenticity of movement when appropriately challenged (like Brett and Grey pioneered), leading to injury prevention, yada yada yada...

So, if you're emotionally attached to the "thing", fine... but try to pause, and hear what is being asked.  Alistair quoted Grey who is asking the same kind of questions about strength and stability: how do we define these "things".  No one has yet to attend to the actual question asked (I guess Zach did, just up top here).

This is a great discussion, and a worthy pursuit.  I come into the same problem as Scientist when I try to describe this very real phenomenon.  Intelligent students familiar with physiology question my description, with disbelief.
 
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