A Unified Theory for Physical Therapy and the Treatment of Pain

[BB]

I wrote the following a couple of months ago at the urging of Nari...

On the Cusp of a Unified Field Theory

I think that our profession is a nation divided. We are many different therapists, using many different methods, to approach similar patients. A person practicing in method A, may work in a very different manner than a person working with method B. Both have success with their methods and therefore assume that it is the best. However, if A is right and B is wrong, then why do both work? And what do you do when neither A nor B work? Many often feel they have to throw out one method if they want to use another, or collect of bag of tricks, a toolbox, to run through until you find the "right one for that particular patient."

I'm not proposing that variation between therapists should not exist. However, a patient might get completely opposing explanations of mechanism of correction between therapists A and B.

We need to start looking for similarities between our treatments. The goal of this process would not be to find best practice, but instead to be able to explain WHY multiple methods work. What is the common ground, the generality between methods that allows both to have success? When this question can be answered then the concept of better practice can begin to be approached.

Inevitably, the answer to this question leads one to the nervous system. One must begin to consider the advances of neuroscience to find a broad enough framework to encompass the answer to the above question. The quest to achieve this understanding can lead one to the ability to answer that question from multiple perspectives. Outside-in and inside-out perspectives that are able to withstand scrutiny from what is known about the nervous system and the advances of neuroscience.

Einstein sought to create a unified fields theory. He reasoned that an explanation existed that would explain the divisions created in physics by his relativity theory. He was unable to find his unified field. However, his findings and his theory have allowed modern neuroscience to flourish. Our own unified theory may be within reach as a result.

[Diane]

Cory,
Thanks for putting up this thread. Very timely.

Occam is reputed to have said,"It is vain to do with more assumptions what can be done with fewer assumptions." In our case, probably fewer body tissues/systems. How about just one? The control system.

Ironic probably, that the very system, the understanding of which could encompass PT fragmentation, unite perspectives, account for similar outcomes from differing approaches, answer disparate questions, is the one that most mesodermal PTs run away from because they think it is too complex. Look forward to others' input on this.

[BB]

This is a task that has been on my mind for some time. Most on this board will agree that a certain shift in thinking needs to occur in the profession. I will contend that this shift can be facilitated through a Unified Theory.

Stating that this is going to be a big task for me is a large understatement. Therefore, as always, I encourage feedback, questions, criticism, etc.

As this thread will have the potential to grow quite large, I will occasionally come back to this page to add an index if needed, for ease of navigating through the information. I will attempt to present in a systematic manner for ease of reference.

I'm going to begin by organizing some topics into 3 categories.
-inside out neuromodulation
-outside in neuromodulation
-the placebo effect

[BB]

I'll start with inside out neuromodulation

I would like to start with an overview of several concepts that I will use throughout the thread. It will be important for these to be presented first.

The first concept that I would like to cover is Antonio Damasio's Somatic Marker Hypothesis. Damasio is a neuroscientist at the University of Iowa, and he presents his hypothesis in the book Descarte's Error.

Damasio contructed the somatic marker hypothesis from his work with patients with damage to the ventral medial prefrontal cortex.

The hypothesis states, that the mind when confronted with the need for any action is supplied with an extaordinary amount of possible actions from which to choose. The process of going through each possibility with costs/benefits computations would be cumbersome to say the least. Damasio argues that each possible action is linked with an emotion and its correlated body states based on past experience. These act as markers for each image. This allows the mind to quickly discard those images that are linked with a possible bad outcome as is evident by their emotional marker. The result is the choices are narrowed down to those that are marked to be the most likely to be advantageous, and therefore significantly reduces the amount of costs/benifits computing time necessary.

Damasio has been able to show in the population with ventral medial pre-frontal cortex damage have lost the ability to bring about the autonomic changes associated with emotion in regards to anticipated action. He tested this in a variety of ways using skin conductance. Chapter 9 in Descartes Error is devoted to testing of the hypothesis. People with medial pre-frontal cortex damage display normal intelligence, are able to describe social constructs properly, but are unable to function normally in a number of important ways. Most relevant, they often spend hours working on mundane tasks, unable to move on. Since they have lost the "somatic marker" that their emotions provide, they are presented with an unfiltered number of options through which they must navigate.

You should note that the hypothesis is not called the emotional marker, but is called the somatic (body) marker. It is called this because the marker consists of the visceral and non-visceral signals associated with emotions. Again, the somatic marker decreases the number of images presented as potential actions. What makes up these images is very important to this discussion and I will return to it soon.

For now, it is important to know that all of this is happening non-consciously. This brings me to the first point:

when you exclude consiousness (or better stated, prior to consciousness), the choice of action is based upon past experience and how the body responded to those decisions. The action chosen will be the one that will bring about the body response best suited to the task at hand, based on previous experience with similar situations.

Stated more simply: given the opportunity and the correct options, the nervous system will non-consciously chose the action that has proven most advantageous in meeting its needs in past experiences.

[Barrett Dorko]

Great stuff Cory. Before long I'll be speaking these words as if they were originally my idea, which, from me, is the greatest compliment I can give them.

I was wondering. Is there any indication from Damasio as to when this previously learned ideal reaction might have been learned? I couldn't find any, and if there isn't, wouldn't earliest childhood be the most fertile ground for such learning? Ideomotion as manifest in adults seems to be a return to this.

I'm reminded of a speech in the movie "Million Dollar Baby" by Morgan Freeman's character, describing how unnatural and counter-intuitive are the movements in boxing -certainly an adult activity. I'm also reminded that Hans Christian Andersen had the words "The Emperor has no clothes" emerge from the mouth of a child.

[BB]

Hi Barrett,

He contends that it is a continual process, but he does have the following to say:

From p.175 of The Feeling of What Happens

In a developmental perspective, I expect that in the early stages of our being there is little more than reiterated states of core self. As experience accrues, however, autobiographical memory grows and the autobiographical self can be deployed. The milestones that have been identified in child development are possibly a result of the uneven expansion of autobiographical memory and the uneven deploymenet of the autobiographical self.

Gotta go now. More later...

[BB]

Back to finish the last post....

I'm going to come back to the idea of "self" as it will play a big part in the discussion.

For now, let me say that the autobiographical self is built on memories of experience, and therefore bring in social and cultural influences. In the above quote, Damasio is saying that, in children, the machinery for memory is still in the process of developing, limiting access to this system. Additionally, the younger the person, the less autobiography has been built. Since in early stages the non-conscious markers have little autobiography to be compared to, they are more likely to be expressed as is.

wouldn't earliest childhood be the most fertile ground for such learning? Ideomotion as manifest in adults seems to be a return to this.

I would think that the learning of this nature would continue throughout life, but the expression of such actions early in development, without the social and cultural constraints from the autobiographical self, and the pure expression of ideomotion in an adult would be comparable.

[BB]

I want to next expand on what images are as they pertain to the non-consicous mind.

Damasio says the following on p. 318 in The Feeling of What Happens:

By the term images I mean mental patterns with a structure built with the tokens of each of the sensory modalities- visual, auditory, olfactory, gustatory, and somatosensory. The somatosensory modality includes varied forms of sense: touch, muscular, temperature, pain, visceral, and vestibular.

In other words, an image is not just a visual picture in our head. It is an activation of the neural maps of all the above mentioned sensory modalities that go along with that choice.

As an example, when you think about sitting in your car, the image that you consider includes the sight, smell, temperature, feeling of the seat and/or steering wheel, body position of sitting, etc. All of these neural maps have been activated in just thinking about your car. It is the architecture of this experience and it is a good example of how our mind thinks in terms of context.

Now if you go back to the description of the somatic marker hypothesis, you will appreciate even more so, the amount of information that is processed in every decision, and how having a marker system (emotion) helps with efficiency.

More on images coming from Patrick Wall next....

[BB]

Patrick Wall was perhaps the worlds leading neuroscientist on pain prior to his death in 2001 after a battle with cancer.

In his book, Pain: The Science of Suffering, he had this to say on p. 146:

Classical theory is that the brain analyzes the sensory input to determine what has happened and presents the answer as a pure sensation. I propose an alternative theory: that the brain analyzes the input in terms of what action would be appropriate.

This is where we are going to begin talking about pain.

We are getting a bit more specific with our images now. Not only are the images provoked consisting of representations of neural maps, they are analyzed in the context of an appropriate action or a motor plan.
Damasio parrellels this in The Feeling of What Happens in his discussion of "objects" percieved as an image, with the corresponding neural maps, in addition to the changes that occur as a result of our relationship to the object, or motor plans for response to the object.

Wall goes on on p 147 to say:

There are elaborate and extensive areas of our brain concerned with motor planning as distinct from actual motor movement. It is precisely these areas that are most obviously active when the brain is imaged in subjects who are in pain but quite stationary.

Let me re-state that: People in pain demonstrate activity in the areas of the brain responsible for motor planning even when they are not moving.

[EricM]

Really enjoying this Cory. I have just one question regarding the last statement. I cite this passage from Wall several times when doing inservices or in explaining pain with patients. To be clear, do people without pain, who are similarly in states of non-movement, not show any activation of motor planning areas? Or if they do, are these studies showing that the patterns of activation are sufficiently different? Is anyone familiar with the finer details of these studies?

eric

[Diane]

I've read that premotor and motor planning areas are active even in thought. Which would be why meditation would be a different form of brain (non)activity.. "stills" the mind. One wonders however if meditation can "still" pain. Maybe Ian will have some info on that.

[nari]

Motor areas are active when imagining movement - hence one can increase muscle bulk just imagining the action - but I don't know the degrees of difference in activity between the groups.

Keep going, Cory - this is good revision and tying up of thoughts!

Nari

[Synergy]

Great topic Cory! I happened upon this article while I was browsing my Yahoo! feeds. I think it's applicable to this discussion.

Mental Activity Seen in a Brain Gravely Injured

[BB]

Eric,
Since the brain analyses in the context of a potential action, both those in pain and those not in pain would demonstrate motor planning activity. Anyone who is "sensing" would display this.

Wall actually goes on to say this on p.148 after describing similar findings in those learning new words by listening:

In the case of pain, the analogy would be that the overt defensive reaction to a noxious input observed in the baby is suppressed in the adult although the pattern of responses is retained as a possible reaction.

(more support for your earlier statement, Barrett!)

The important thing to take away here, is that sensation is expressed in the form of a potential action.

A great example is given describing those who have suffered a stroke resulting in left side neglect. These folks cannot sense anything that is on the left. They will even draw only the right side of a picture, cannot recognize their own left hand, etc. Wall describes a remarkable finding on page 149:

Italian doctors, whose results were confirmed by many others, discovered that stimulation of the vestibular system in the ear completely resotred all sensation on the left side. It disappeared again as soon as the stimulation stopped. What could be going on? The vestibules in the ear continually inform the motor system about the body's position in the up-down and sideways directions. It is our major organ of balance. it is obvious that the map had not been destroyed in the patients but that they did not have the ability to refer to the entire left side of the map. How could that be? Disturbed messages from the vestibular system, which controls sensory motor posture, had slammed the frame of reference for the whole brain so far the the right that it was unable to perform both its sensory and motor tasks on the left side. It is apparent that we can sense only those events to which we can make an appropriate motor response.

bold mine

Quite a profound finding.

What makes this situation in pain different from other sensations, is that it in pain when the action is met the sensation is terminated and cancelled. The sensation of pain needs to have it's motor plan satisfied. This is what makes it a need state, like hunger and thirst.

Much more on this when we get to placebo...

Chris,
Made me think of Locked in syndome. A quite sad, and interesting condition. Sometimes they are thought to be commatose until someone notices that their eyes are moving. They are completely conscious, yet can only move their eyes up and down. Damasio talks about the condition in The Feeling of What Happens.

[nari]

I have seen and treated quite a few locked-in patients, and without fail, the spouse or friends report: "I know he/she is awake"! and no-one takes any notice for days. They do, after all, know the patients better than anyone else.
I noticed that there was something different even when they weren't moving eyes at the time; couldn't pinpoint it, but the patient seemed alert. It is a strange thing.

Nari