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The Thinking Practitioner Podcast:
Episode 27: The Little Man In Your Brain: The Sensory Homunculus

Broadcast date: 11/25/2020
©Copyright The Thinking Practitioner Podcast, Til Luchau & Whitney Lowe

Whitney Lowe:

Hi, this is Whitney Lowe and ABMP is proud to sponsor the Thinking Practitioner podcast, all massage therapists and bodyworkers can access free ABMP resources and information on the Coronavirus and the massage profession at abmp.com/covid19. Including sample release forms, PPE guides, and a special issue of massage and bodywork magazine, where Til and I are frequent contributors. For more check out the ABMP podcast also, which is available at abmp.com/podcasts or wherever you prefer to listen. So hi Til, how's it going today?

Til Luchau:

Really good, Whitney. How about yourself?

Whitney Lowe:

Very well today. We've got some neurological things that we're going to try to take a deep dive into today, if I understand correctly?

Til Luchau:

Neurological that have a lot of implications out into the body of course, and for us as hands-on therapists. I wanted to pick your brain a little bit and think through this idea of the cortical homunculus. [crosstalk 00:01:18] The little man in the brain. Homunculus means a man like figure in Latin. Is the part of the brain that is primarily thought to represent, you could say the body both in terms of motor control and sensory information. Most of our listeners probably are familiar with it, and once they see the picture. There's some 3D pictures around showing a distorted human form with really huge hands and face and lips and tongue, because those are the part of the brain it turns out that have much more area dedicated to them. So this little man, this little sculpture is made in proportion to that and is distorted in that sense.

Whitney Lowe:

Yeah. So we're going to try to dive into some pieces of what the homunculus is, what it means, and I assume we'll try to touch base on some clinical applications and relevance for that as well. Maybe you can lead us a little bit more into where did this come from and how did it come about?

Til Luchau:

This is an interesting story and that's, what's made me want to do this for an episode. There's a paper that came out, we'll put the references in the show notes, but the history of it is interesting. It was Penfield who in the 30,s, Wilder Penfield a neuroscientist was using electrical probes on brain surgery patients to try to map out on the brain, which parts of the brain were say dedicated to which parts of the body. So his method was pretty crude. People had to be awake for brain surgery so they can monitor their cognitive functioning. They just had local anesthesia, but he and his assistants would use the electric probes to touch parts of the brain and then they'd ask the patient, "So where do you feel this?" Or they'd watch then see which part of the body twitched, and then they just start keeping these logs, which turned out to be pretty extensive over a lot of years.

               A couple of hundred patients, if I'm remembering correctly and just started to look for correlations like, Oh, when we put touch that part of the brain on a bunch of people, they all felt it in their arm. So that's how this map came about through actual electrical stimulation directly on the brain surface, and then reports from the patients on the table about where they felt it.

Whitney Lowe:

It seems too, a tremendous amount of complexity to this because when we think about what is necessary for the brain to govern both sensory information and motor information, this is one of the things that I think comes up in sort of comparative physiology. When we talk about the brain to body ratio size in various animals compared to, we often compare it to ourselves and there are very few, and I don't remember specifically, but there's like two maybe animals that have a bigger brain to body ratio than we do. Very close in size, I believe. Dolphins and I think it's one of the whales.

Til Luchau:

Killer whales.

Whitney Lowe:

Yeah, but interestingly, it seems to be so much of this involved with both motor skills and a lot of the sensory cortex processing of those kinds of things. This is something where I think the homunculus is a really interesting concept. Somebody said something one day to make a comparison that we're talking about how much brain power is used to do different things, and they said, which would you think to be a more complex, cognitive skill? Beating a world-class chess champion or walking across the floor?

Til Luchau:

Chess champion.

Whitney Lowe:

Initially, I think, well, sir, certainly beating a world-class chess champion is a lot more cognitively challenging, but-

Til Luchau:

Depends on what you mean by beating, I suppose. Beating at chess? Yeah.

Whitney Lowe:

Yeah. Yeah. At chess. Yeah, that's right. Because, for example, we have been able to create computer programs that can beat a world-class chess champion at chess. We've had a very difficult time creating artificial motor activity in robots, for example, that can walk across the floor without falling down. I think this is one of the things that emphasizes how incredibly complex that so matter sensory motor cortex is, in processing information.

Til Luchau:

Yeah. It's interesting to look at the relative size of this representation of the homunculus and say, as you said, there's a lot of processing zone dedicated to the hands and to the face. Those are the huge zones that require chess champion quality kind of processing just to function normally.

Whitney Lowe:

Yeah. Here's something I have a question about. I have to admit, I haven't really studied the homunculus enough to make that comparison note. Clearly when you look at the sensory maps of the homunculus, the face lips, tongue, very large out of size proportion, but when we talk about the motor capacities, obviously the hand needs tremendous motor capacity because of the fine precision movements that the hand is producing. It doesn't seem like there would need to be a similar type of motor expanse for the face, lips and tongue, although I guess maybe when you think of language and those kinds of things, there's a lot of specificity to it, to the motor activity there as well.

Til Luchau:

All right. That's a really interesting question. Does the mouth need as much brain area for motor as it does for sensory? Is that what you're asking?

Whitney Lowe:

Yeah. I think we can bypass the comments about people's mouth's needing sensory cognitive capacity [inaudible 00:07:03] necessity of motor skills.

Til Luchau:

Yeah. I like the question, but this is the trap, let's say, that this map draws us into, because we start to think about this picture that's been so common is called the most popular and most reproduced figure in neuroscience as being a map of the brain, and it's not. It's a map of these guys experiments back in the 30,s, imperfectly recorded. So some of the thing that surprised me is how inaccurate it is, but your question is, does the mouth [inaudible 00:07:41] need as much motor, well, apparently on their maps, at least the hand has a lot of both sensory and motor, and so does the mouth. They're both big and there's some differences on their map between the sensory and motor homunculi, the differences, but it turns out as I dig into the specifics of it, those are pretty darn in exact.

               In fact, there's a lot of overlap. If you look on some neurology illustrations of the brain, you can find parts of the brain colored sensory cortex and another part colored motor cortex. Well, it turns out it ain't like that. There's a lot of overlap between those two regions. A lot of things that happen for sensory function, also involve the motor part of the cortex. Or they got stimulus in both zones, you could say.

Whitney Lowe:

Yeah. One of the things that-

Til Luchau:

Well, let me just say one more thing about that. It turns out that those are linked a lot more by function than by territory, so that you find functional positionings within the brain. Like hand to mouth, you're feeding yourself a lot or you do a lot of stuff with your hands and your face. That's one reason that they're so close approximately in this map, and one reason they're so involved with each other as well.

Whitney Lowe:

Yeah. Do you happen to know, and I have no about this, if some of the more modern diagnostic studies that maybe functional MRI and things like that, which can show parts of the brain lighting up during different activities or things, have they been able to confirm most of the accuracy of those maps of the homunculus?

Til Luchau:

Yes and no. It's no in that their models are much different. These guys back in the 30,s made a cartoon and said, this kind of represents what we're doing. Penfield to his credit, never really put it forward. It was buried in his original paper in this one small little illustration, but people latched onto this little picture of a guy distorted in a weird way, upside down on the brain and a bunch of other things. He kind of tried to back away from it saying, well, this was just kind of a rough sketch. Like I said, it's been so used because it communicates so clearly to us. Oh, there's parts of my brain that relate to my body and they're not in proportion to my physical body. They're out of proportion. So yeah, the more recent studies with FMRIs and also transcutaneous magnetic stimulation and inhibition of the brain, show a much more complex picture that doesn't make a very good cartoon.

               They make a more complex diagram of interconnections more than territories, because that seems to be more significant as how things are connected up than actually where they map on the brain surface.

Whitney Lowe:

Too, I would imagine there is also when we talk about neuroplasticity and the capability of the brain to adapt, let's say after some type of injury or impairment, we see a lot of instances where neurons and new synapses can sort of make connections to places they weren't before. So perhaps this map is not quite as permanent as we might initially think and has got the capability or adaptation and evolution over time as well.

Til Luchau:

Yeah, well, I mean the neuro-plasticity people 10 years ago and still to this day, make a big deal of that. That it turns out there's some really interesting studies of violin players who have really big left-right differences in the amount of brain dedicated to their hands, because you do a very different thing with your left hand, playing a violin than you do with your right. So the hand that you use a whole lot more, has a much bigger representation in the brain than the one you don't. Then, [inaudible 00:11:18] varies a lot between people and what they do with it, but then if you stop playing as a violinist, your brain proportions revert to more of a standard size closer to the average, pretty quickly within two weeks there's a noticeable change in the amount of brain dedicated to your playing hand.

               Then resuming practicing in these experiments, the amount of brain grew essentially, or remapped into more areas of the brain to have a finer control and more of the brain dedicated to that hand again, within another two weeks. So there seemed to be like in this study, a two week threshold between use it or lose it. If you're not practicing a whole lot, you start to get rusty. You don't have as much brain dedicated to your hands. You go back to practice and you start getting a whole lot more brain dedicated to your hands, but there's a lag. There's a couple of week lag before it's back to normal.

Whitney Lowe:

I mean, still, I would consider that fast changes if you're talking about different parts of the brain development and the capability of doing that. I mean, it makes absolute sense in terms of why we can sort of not be so great at a motor skill that we used to be better at and then come back and eventually polish it back up and rebuild it once again. Fascinating ideas there and some obviously implications for soft tissue and hard tissue damage in the body where you're trying to compensate for areas that are not able to function the way that they used to.

Til Luchau:

Well, there is a lot of compensation that happens even in brain injuries that other parts of the brain take that over, which is one of the criticisms of this map. It's not a one-to-one relation, it's not a little voodoo doll where exactly this place equals that place in the body. There's such complex interconnections that even when there's brain damage, other parts of the brain takeover and do that job that at least on their map, they assigned to the hand or whatever.

Whitney Lowe:

Yeah. That just made me think of something. I'm curious to hear your opinion about this. When we were doing a podcast, you and I together, or a presentation where the IBMPC summit recently, and we got a question about reflexology that came up and this is a concept or a conceptual idea. You take foot reflexology where there's supposedly a map of organ systems based on certain parts of the foot. So with all this neuroplasticity and capability of things moving around, it's curious how those kinds of systems would be able to formalize a consistently presenting map from each individual that maps on a regular basis to those particular areas.

Til Luchau:

Good point. Yeah. We're learning things change a lot according to function. There's lots of individual variation and that the maps are never quite as simple as they look on paper. Now on the other hand, and the authors of that paper made this point, there's actually, you could argue it both ways. You could say that yeah, maybe the foot does have a whole body map on it because the brain does and then in traditional Chinese medicine, the ear does. The whole body's mapped on the ear. They said, well, why don't we take any part of the body and I bet you could find some correlations, interconnections and functional mappings onto its surface for the whole body.

               Why not the eyeball? So there is a kind of holism at work or a fractal reproduction of control and sensory things. It does seem to actually, have some plausibility down to those small scales, now whether that's literal truth or just an interesting mental exercise, is an interesting conversation.

Whitney Lowe:

Yeah. Yeah. That gets into a lot of those discussions of people with amputations and things like that, that still can feel missing digits and those kinds of things. Clearly there are some somatosensory maps that remain intact for all kinds of things like that.

Til Luchau:

In fact, there's, I'll put up a reference again in the show notes, because this is one that came to mind when we picked this topic. Story in the Smithsonian magazine a few years ago, the headline, this woman was born with three fingers, but her brain knew all along what having five would feel like. So this is a story of a woman that was born with three fingers, had an auto accident where her three fingered hand was injured and in the rehabilitation process and the pain she had afterwards, it became clear that she could feel five fingers.

Whitney Lowe:

Then, did she have three fingers on both hands, or she had five on the other hand as well?

Til Luchau:

Five on the other hand, but three on the hand that was injured. Again, she had a sensory hand with five fingers, and then as the rehabilitation went on that actually that sensory hand developed and changed in size in her perceptive field, et cetera. It brings lots of questions like are we born, you could say with a sensory map, that's based on something other than our physical form, is there some sort of sensory or motor map that's based in the brain, perhaps-

Whitney Lowe:

Yeah. How is that potentially influenced sometimes too, by all kinds of other perceptual things. I think you had put something in your show notes, and I was going to allude to this too about things like the mirror therapy, where you have or some of the other visual distortion therapies that are trying to get people to address pain complaints by doing certain things to make their brain think they see something different than what's really happening there, it seems-

Til Luchau:

Rubber hand illusion.

Whitney Lowe:

Yeah, rubber hand trick and all those kinds of things. There was one that somebody described one time too of a visual box of some kind that they were doing with an arthritis treatment. Where they got the person to put their hand inside this box where they could see their hand and then the practitioner grasped the end of their fingers and gently pulled on their fingers, but the visual representation was that their finger was really getting longer and longer and sort of stretching out and they said it was incredibly good feeling for this person who had arthritis that sensation of they're just taking all the pressure off those joints because it was getting pulled and stretched out. Of course, that wasn't really happening, but-

Til Luchau:

Really revealing your bias toward physical reality, Whitney. I'm using the word really there, because you can say that it was really happening in a perception. She really thought she really had the experience, but no. Would a third uninvolved observer agree? Probably not. It does bring up all those questions of what is really "Happening." If we change people's perception and change their experience, is that sufficient perhaps? Is that enough? I got to say, I'm at that persuasion. I'm of that, bias that says yeah, if my clients are coming with a subjective complaint, like pain and I can influence their pain whether subjectively or whatever. Good enough for me. In my way of thinking, this is a major map and major tool, this idea that there's a representation of the body that we're working with in the brain, not always even the physical body or the actual tissues, that one of my goals is to actually influence the representational and experienced aspect of the body.

Whitney Lowe:

Yeah. So tell me about that when you're working of, a way in which you might think about that being a goal of trying to shape, mold, modify, or maybe call awareness to. Even that representation. How do you kind of go about that or what's your sort of strategy for accomplishing that?

Til Luchau:

So let's say something like hand pain or wrist pain, or something that we might suspect being neurovascular compressions and carpal tunnel syndrome to say something like that.  One approach is say, let's look at what might be mechanically compressing the nerve vasculature and go to mechanically change that compression. The other approach might say, okay, so let's look at how their representation in the brain has been impacted and has maladapted to that extra sensation that still might be coming from compression or overuse or whatever, but as resulted in an altered brain map that keeps going to pain and keeps going to disability or weakness or whatever it is. So right there, I have a different model or different therapeutic target from not just tissue to being brain as well.

               The actual procedure I might use would involve, the metaphor there is like a coloring book. Where I'm looking to find ways to recolor the client's brain map with a different, more pleasing color than they've found so far. So touch is really good at producing pleasant sensation and pleasant experience and essentially metaphorically, recoloring the brain map.

Whitney Lowe:

So in doing something like that, it would seem to me also that this might extend beyond just what you're doing with your manual manipulation of soft tissue and also include what you're saying to your client's pictures, visualizations, metaphors, et cetera. So how do you see that play into what-

Til Luchau:

I mean, like we said, I think on a recent one, we're experienced architects. We're not just tissue technicians, we're really creating a whole experience for our clients that involves like the room, the way I'm talking to them, the setup, all of the intake procedures. All those things, the therapeutic reliance, of course, all these contextual factors that essentially prime the pump for them having a certain kind of experience that's satisfying and relieving of whatever symptom they're trying to address, whether it's stress or pain. Yeah.

Whitney Lowe:

I think in many instances, something like this perceptual awareness or knowledge of the complexity of some of these, maybe let's say just on the sensory level of person comes in and complains of a certain type of pain sensation in one of these areas, which is richly innovated and richly represented in the homunculus. In another experience, we did some interesting studies when I was in my psychology graduate program with two point discrimination, which is how close two different contact points can be before you can tell or how far away can they be before you can tell it's two different things. Like if you get up the two points of a compass, really close together and you touch somebody's skin, it may feel like one point until you get a certain distance away and then you can clearly tell it's two separate discrete points.

               The two point discrimination is really small on, for example, the tip of your finger, but it's much larger on your back. It's a lot harder to tell those things on your back than it is on something like your fingers. So this comes into play, as we think about when people have pain in certain areas. Maybe that significant what's happening in some areas might need a different type or focus of their intervention because that sensitivity is not quite as extensive as it might be in another place like the hand, the fingers, the face, or one of those other areas highly represented by that.

Til Luchau:

Yeah, I'm going to take a little branch off your thought tree you're developing there. I like what you're saying, but two point discrimination is really fascinating. You could look at this sensory homunculus as a map of two point discrimination, and it does correlate pretty well. The bigger areas on this map have smaller measures of discrimination. Like you said, on your fingertip, you can tell when things are really close together, your fingertips is huge in your brain. On your back, it has to be pretty far apart before you can tell that you got two points and not just one and back is really small on the brain. So then in pain, it's pretty well established that when have pain, counter-intuitively your two point discrimination measures go up, it gets less refined.

               You need a much bigger distance between two points to even tell it's two points. Even though you're more sensitized and more sensitive, you can't tell what you're feeling. It feels like one thing, even if it's two until it gets really far apart.

Whitney Lowe:

Yeah. That has some other implications too. I did some very unofficial experiments from time to time when I was looking at the use of pressure tools for people who are saying like, I need to find a way to not burn my thumbs out all the time. Looking at the different pressure tools that were out there and I did some experiments with multiple clients saying, tell me when this is a thumb and tell me when this is the pressure tool that I'm using in there. Clearly when you're working on somebody's back, it's a lot harder for them to tell a difference between those types of things. So this is a great thing that says, you can use a lot of different tools and get the same type of effect in many instances without feeling like you're having to burn out the use of your hands and thumbs and fingers sometimes.

Til Luchau:

You're saying why burn out our thumbs on an area they're not feeling that acutely? [crosstalk 00:24:53] Let's deal with efficiency.

Whitney Lowe:

Yeah. Break out the screwdriver. Yeah.

Til Luchau:

Something. Well, so the two point discrimination thing is interesting because people have a larger distance, less discrimination. They can't tell if the tool or your thumb. If they're in pain, they get less refined. So it stands to reason in my mind that refining perception will help with pain tolerance. Now it turns out, I've looked hard. There haven't been those studies that have been definitive to say yeah, if we get someone really getting better, at two point discrimination, does the pain get better? We know that it gets bigger when we have pain. We don't know that we can make it smaller with training and practice. You can get better by two point discrimination, does that make pain better? In my experience, yes. Because I often will have people report on the table what they're feeling or describe it to me, and I'll work around the edges of their zones, where they have that shift and discrimination and we get a pretty clear change in the location of that zone, where they can feel accurately where they can... Are there studies that validate that? There aren't yet that I know of, unfortunately.

Whitney Lowe:

So as we talk about that thing about discriminating differences between some of these zones, you had mentioned something in our notes here, too, talking about smudging. Tell me about that, cortical smudging.

Til Luchau:

Cortical smudging is the similar idea that the map in the brain gets smudged, if they could imagine like a charcoal drawing, getting smudged or a picture being out of focus when there's pain. That map is out of focus, and so there's blurring you could say between more areas. Maybe one finger hurts at first, and then it spreads out into the neighboring finger. Like that map gets blurred. Butler and Moseley use this idea. They explain pain folks... A lot of people have done that. Idea's been around for at least a decade, maybe more. It's a useful map. It probably doesn't have as clear a correlation to what's actually happening in the brain, as we would wish. There's more evidence that it happens at a motor sense that you get when you have a disability or motor impairment that motor map gets smudged or blurred, so that more parts of the body get involved. More parts of the brain rather get involved in trying to move that part of the body.

Whitney Lowe:

Again, this is somewhat anecdotal, but I think we can see similarities oftentimes with many chronic pain patients who have greater difficulty specifying exactly where something hurts. They'll just say, it hurts all over. It's all through this whole area and that seems to be, I think oftentimes indicative of the cortical smudging in there. I was curious about [crosstalk 00:27:47]

Til Luchau:

Well, I'm jumping in. So useful because then I can really, as a mental map, at least nevermind the research for a second, as a mental map, I can really work to help my client feel that more accurately, which is counterintuitive. If something hurts, people don't want to feel it and they want you to just make it stop hurting them. We often want to, but if we take time to actually have them describe the pain exactly where it hurts and where the pain stops and actually work with touch to help someone really get clear on that in a pleasant, non noxious way, that shifts the pain experience so much that it diminishes it's an unpleasantness for sure. Often it's intensity as well.

Whitney Lowe:

Absolutely. That's exactly where I was going with this because I think this is something I don't know that we have seen research to do yet, but there has been suggestion that some of the very specific soft tissue manipulation strategies might have a benefit in sharpening that cortical map and decreasing the degree of cortical smudging in there. Like you said, it may seem counterintuitive that people would want to be specifically honing in on those sensations, but there's a good reason that a lot of times people say, "No, just get in there and work that thing." Just that particular way, because there is a desire, an innate desire to try to feel like something's being done to it and sort of cleaning things up to some degree. I think that's a real significant benefit of highly specialized and specific soft tissue manipulation work.

Til Luchau:

You're scratching that little man's itch in a way, by giving some tactile stimulation to those places that are distressed. So I can totally see that. I think we should put in the disclaimer here that it's not just about stimulating any sensation there, because you can stimulate sensation just by poking something or just like you said, like you're joking, get out your screwdriver. It's actually recoloring, it's a different kind of sensation. It's more refined. So it's more exact, you need the smaller brush and different color. If the pain could be visualized as being red or orange, and by the way, pain is not orange or red, despite what all the clip art pictures show. Whatever the color it is in your client's imagination to actually shift that hue, shift that color tone a little bit. It can be really remarkable too, in terms of the in tensity, pleasantness thing.

               Can I say a little bit about that?

Whitney Lowe:

Yeah, absolutely.

Til Luchau:

Well, it turns out that these parts of the brain which are located up in the parietal lobe, these parts of the brain that are S1, M1. The primary places that are mapped out in Penfield's map, what they map mostly is intensity. They map the intensity of experience, not whether it's pleasant or unpleasant, that happens somewhere else. That's more anterior cingulate cortex, more the insula, because that pleasant, unpleasant, valence has a kind of emotional quality or a reactive or evaluative quality and that's a different part of the brain than just gets a pure somatic sensation. Which is fascinating because pain has both. Pain has an intensity and it has, do I like it or do I not like it?

Whitney Lowe:

Yeah. This is one of the key things that I think makes so much of what we do very difficult to study and duplicate in research contexts, because so much of the benefits of the interaction that happens is about that quality that you're talking about. That's tapping into those areas because you can massage, for example, is not something that you can just say is consistently applied between five different practitioners if they're all taught to do the same thing, even. The way in which they contact, touch the body and interact with that individual has absolutely a huge amount to do with the way that perception or that treatment is received and perceived by the individual. So we're not like an ultrasound machine that you can test and say, this actually has this kind of effect, because so much of it is dependent on who the individual is and how it's conveyed.

Til Luchau:

Well, a lot of the studies trying to tease out the mechanisms do need by definition, need to get really precise in their mechanical measurements. So they'll have robot arms, or very careful measurements of pressure and direction and speed, and such, but this pleasantness, unpleasantness, valence that the rest of your brain is doing is influenced by so many things other than those mechanical factors. It is all the contextual factors. It is who you are. It's what's happened before. What you think is going to happen after. It's all those things coming into it. This an interesting footnote here, there was a study of pain and THC awhile back that actually revealed an interesting effect, in this case, THC around pain. THC seemed to have a significant effect on pleasantness, unpleasantness, but not in this one study a significant effect on intensity. Yeah, weird, but it hurt just as much, but it didn't bother you half as much.

Whitney Lowe:

Uh-huh (affirmative). I'm sure we could get lots of discussions about what the amount of THC you have that influences whether or not that bothered you a whole lot.

Til Luchau:

It's interesting. Yeah. Whether you could take that one steady literally, and there's been other studies that didn't replicate that, but that's an interesting concept too. A touch might do that. A touch might change the color, not necessarily the intensity of the color. When we can, we want to change the intensity of the color. We want to turn down that pain intensity and so many manual therapy things can do that. They can just erase the pain or diminish it down to such a small percentage that it's not even a bother, but when we can't then often the plan B is, well, let's work on changing the color then. Let's work on changing the pleasantness, unpleasant ratio.

Whitney Lowe:

I want to take just a very quick little diversion, because this is a huge, big topic, but I just want to touch on this as we're talking about it. We're making a lot of references to things that make our therapeutic interventions more or less successful with our clients and a lot of these things having to do less with the exact way by which we manipulate soft tissue and a lot more to do with persona being conversation, discussion or whatever. Yet we don't have, in my opinion, a lot of consistency or even really skill buildup in our training programs about how to teach people to do this well. I just wonder, how do we get there? How do we get to the place of really teaching those people? I think a lot of it is those subtleties and fine points they get taught to you in continuing education later on after your initial training. I'd love to look at how we can better focus on those kinds of skills in all of our training programs, regardless of the disciplines.

Til Luchau:

Well, I defer to you, but I also digress. I think maybe we do a better job of teaching it than we realize. I think we could do much better. You're much more familiar with say the training in schools and curriculum environment than I am. So that's why I defer to your sense of that, but I'd say just to argue the other side of the equation, we actually do a decent job because all of the soft skills that get taught and all of the inductive skills that get taught through modeling and practice are what we're talking about here. There are the things do shift someone's pleasantness, unpleasantness, valence for their sensation in a way. It isn't just like the right angle and the right technique and right duration and the right SOAP noting, and it's not just all the technical aspects, which are also essential. How do you create a cohesive transformative experience for your client?

               I think there's schools that are teaching that effectively. I see some pretty darn practitioners coming out of our system. What do you think?

Whitney Lowe:

I probably am a bit more critical of this than, because I'm always trying to look at how do we do it better and I realize that there are significant gaps in this. I do see a lot of people coming to our continuing education experiences that I feel like are highly deficient in their initial education. I think there's just a lot of gaps in places that we could improve there, but I do think you're right, that there is a good bit of focus throughout different facets of the subspecialty areas within our manual therapy fields that do put a lot of attention on this. It's much more difficult for example, to create a training models and methods that focus on these things, as opposed to saying like, we've got to cover the nervous system in our anatomy and physiology class, it's just much more challenging to do that.

Til Luchau:

It's not as clear as how to teach it, especially how to break it down and make it consistent, which I know is a value you hold as well. Is how do we make it standardized enough that it can be, have a certain skill level and standard that goes across our field. That is a much more difficult proposition because historically in our field, as well as others, so much of that comes through, like I said, the modeling pieces, the transmission or induction process where you get indoctrinated essentially into a kind of viewpoint that for better or worse gives you a certain way of working in a certain style, then see the proven effective or proven worst case, of course, limiting.

Whitney Lowe:

Yeah. That is inherently the benefit of working with mentors and other individuals who have a lot more clinical and life experience, both of being able to recognize some of those subtleties and fine points of how you do those kinds of things. Sometimes it's really, really small things in the communication of just the way that you make eye contact or the way that you listen and have an empathic caring attitude towards somebody that really, really makes the big difference there.

Til Luchau:

You've named a couple of really important ones. I'm just thinking in our trainings, we have like these little notebooks with a page for every technique. It's got a picture of the page, it's got the description. It's really clear. People love it. They can take their notes. I got that technique. We don't have that for all those skills you just mentioned. We don't have [inaudible 00:38:22] on one page. Turn the page, listening skill on the next. Those are much harder to chart out in that linear way, but maybe there's certainly in the learning phase, there's a place for that as well. Spend some time on that as well.

Whitney Lowe:

So what else have we not touched on here in terms of clinical applications or anything else that you can think of that-

Til Luchau:

Yeah. A couple more trivia pieces and then, for sure some of the limitations involved. It turns out left, right visual recognition of body parts is influenced by pain. This is probably related to the sensory motor homunculus, that if you see a picture, let's say your wrist hurts. You see a picture of a hand, your ability to say accurately is that a right hand or left hand is measurably different, if you have pain in your own wrist. There's some interesting software put out again by the NOI Group and the Explain Pain people to play on this. They show you flashcard, pictures of a hand, you got to really quickly tap the buttons. Is that a right hand or a left hand? The hand that you have more pain in, is going to be a slower time. You can see it right on their app.

Whitney Lowe:

Huh. Interesting.

Til Luchau:

It's bizarre. After this, you can actually increase your time. You can get better at recognizing right-hand, left-hand differences and they show you all different kinds of angles and hands doing different things. So that left, right recognition measures like the two point discrimination one, where it does seem to be tied to brain function in a strange way that when we reverse engineer it, when we get better at recognition, the pain seems to get better as well.

Whitney Lowe:

Yeah. Fascinating. Lots of places of thinking about how we apply these concepts to our more traditional training methods and things that we've been doing to enhance our effectiveness and I think maybe sometimes help explain why sometimes things worked and why sometimes they didn't work with certain people because there's a lot more going on here than just what we tend to see with the physical manipulation of a soft tissue for sure.

Til Luchau:

A whole lot more going on and I'm just thinking there's a role for letting my clients watch what I'm doing. I used to say, put your head down. I'm working with your foot. Just feel it. Part of that came from the alignment idea that we want the body to be in that state of alignment that I was trying to induce, but anymore I'm saying, watch what I'm doing because the mirror box idea, you get so much out of the visual input as well as the [inaudible 00:40:52], but you're remapping the brain with that. Just one more piece of trivia, your brain is inflamed. Those parts of your brain are inflamed in chronic pain. There's a difference in inflammatory activity of the glial cells and people who have sciatic pain in the brain, in that sciatic region of their brain. So it's not just processing, there's a different physiology going on in the brain there as well. Which has lots of implications too.

Whitney Lowe:

So you mentioned too, a moment ago that may be, we've talked a little bit about this, but what are some of those other limitations of our little man homunculus or other things that we'd want to keep in mind clinically about this?

Til Luchau:

The big one is Krzyzewski's idea that the map is not the territory. It's so easy to get wrapped up in the literalness of any map we use and forget that, that's not... It's just a map of something else that something else is what counts. Like I said, Penfield himself was saying, this is just a doodle in page 37 of my study. It's not the way the body works. It's just a conceptualization. So it's important to keep that in mind. This down to the level of like on this 2D map that you'll see a lot of the man stretched upside down over the brain or body stretch of the brain, those body correlations are pretty approximate and are overlapping. A lot was made a few years ago of the genitals saying being next to the big toes on this map, I'm not even going to try to explain that, but there's a lot of places you could go with that idea.

               Well, it turns out it's probably not literally the case anyway, in spite of all the interesting experimentation that might engender, but it's true for the rest of the body too. You don't want to get too wrapped up in like, Oh, this is this part of the brain, which I think is probably related to what you were saying about reflexology and these other maps too.

Whitney Lowe:

Yeah, because we could see the coming on of all kinds of different reflexology systems as a result of that.

Til Luchau:

Well, there probably are and they're probably effective for various mechanisms. It's been really hard to tease out the effectiveness of modalities, even though we can tear apart their mechanisms. So the 3D map though, that sculpture, you'll sometimes a picture of a man and distort a sense, that's more accurate than the 2D guy stretched across the brain, just because it's got proportions. The proportions seem to be reasonably accurate in Penfield's map. There is a whole lot more brain dedicated to the hands and the mouth say, than there is to the back.

Whitney Lowe:

Yeah. We've been talking predominantly about this from the standpoint of the client's perceptual sense too, but I just want to also call attention to the idea that there's another big reason that we want to really pay all of our attention to what we feel with our hands, as we're doing the various different types of approaches, since we are manual therapists. There's a lot that we can refine in that whole palpatory sense and the conveying of certain types of things, as you're trying to access a particular deep structure somehow. It's lots of things that come into this with the level of sensory complexity from our hands in the work that we're doing.

Til Luchau:

That's so true. Then the ways we use our hand or the parts of our hands we're used to using are probably more refined and developed in our own brains and [crosstalk 00:44:18] all the time. In training, people have to try to use their hand in different ways. It feels really weird. Your brain just hasn't shaped itself into that pattern yet, but with practice, maybe it's that two week thing, with practice you get so that you can feel just as sensitively with a different part of your hand than you're used to.

Whitney Lowe:

Yeah. Yeah. That's what we were talking about. People having to learn to do different types of work sometimes because let's say, their wrist hurts, their fingers hurt, their thumb hurts or something like that. They've overused something, they have to try to learn how to do something different, we can certainly. That whole idea we can expand into much different ways of working and methods that will still be able to give us some degree of sensitivity in there, but it might take some time. It might take some time to really work through it.

Til Luchau:

Maybe fascia isn't as plastic as we thought it was 20 years ago, but the brain is a whole lot more plastic than we even realized it's changing all the time.

Whitney Lowe:

Yeah. Which gets us back to your statement from our episode, many episodes ago about perhaps the most important tissue that we're working on is the one between the years. So I liked that again.

Til Luchau:

So there we go. Another tool in that toolbox, another episode. About that. That's what I got. What do you think?

Whitney Lowe:

I think that's a pretty good dust up of the little man. I think in some applications, thoughts and ideas about how he relates to what we're doing so we'll see where that takes us and see what we hear from other folks about that and see where we want to take it from further discussion somewhere down the road as well.

Til Luchau:

Lots more to talk about. Lots of interesting implications. I look forward to hearing back from people. Also, our wrap-up sponsor today is Handspring Publishing, and thanks to them, because when I was writing a book, I was looking for a publisher. It's a big search for a new author like me and they were interested. They gave me an offer. I got another offer from a much bigger multinational media conglomerate. I ended up going with Handspring's offer because they really were helping me write the book I want to write. I'm glad I did because their catalog has emerged as one of the leading collections of professional level books written, especially for bodyworkers, movement teachers and all professionals who use movement or touch to help patients achieve wellness, as they say.

Whitney Lowe:

Handspring has a new instructional webinar series called moot learn, which is a regular series of 45 minutes segments featuring some of their amazing authors including a recent one from Til, so head on over to their website at handspringpublishing.com to check those out and be sure to use the code TTP at checkout for discounts. So thank you very much Handspring and our other sponsors for the podcast as well. Also, would like to say a big thank you to all the listeners who've continued to take on downloading the podcast, listening to it. We're getting close to, I think Til you told me the other day, getting close to 50,000 downloads.

Til Luchau:

Yeah, we passed that mark. Like McDonald's we have a sign that we can put up, 50,000 downloads.

Whitney Lowe:

Oh yeah. So stop by our sites for show notes, handout transcripts, and the extras over there. You can find stuff over on my side, at the academyofclinicalmassage.com and Til, where can people find out stuff from you there as well?

Til Luchau:

advanced-trainings.com. advanced-trainings.com. Let us know your questions about the episode. Things you'd like to hear us talk about. You can email us both at info@thethinkingpractitioner.com or look for us on social media. I'm at my name Til Luchau. How about you Whitney?

Whitney Lowe:

I can be found on social also by my name as well, Whitney Lowe. You can follow us on Spotify, rate us on Apple podcasts or wherever else you happen to be listening and please share the news, tell a friend, and we look forward to hearing from you and we'll dive into some more other interesting topics here again.

Til Luchau:

Thank you, Whitney.

Whitney Lowe:

That sounds good. We'll see you in two weeks.