Melzack and Katz, Pain. Part 5: Pain and purpose

The paper, Pain.

Part 1 First two sentences
Part 2 Pain is personal
Part 3a Pain is more than sensation: Backdrop
Part 3b Pain is not receptor stimulation

Part 3c: Pain depends on everything ever experienced by an individual

Part 4: Pain is a multidimensional experience across time

To everyone who has hung in there with me, so far, we've made it through the abstract!

And now we continue. 

The introduction is as follows: 

"We all know that pain has many valuable functions. It often signals injury or disease and generates a wide range of behaviors to end it and to treat its causes. Chest pain, for example, may be a symptom of heart disease, and may compel us to seek a physician's help. Memories of past pain and suffering also serve as signals for us to avoid potentially dangerous situations. Yet another beneficial effect of pain, notably after serious injury or disease, is to make us rest, thereby promoting the body's healing processes. All of these actions induced by pain—to escape, avoid, or rest—have obvious value for survival."

Do we? Really? 

I dealt with this idea a bit in Part 1. Yes, chest or trunk pain will drive one off to see somebody. Is it the pain itself, though? or is it the fear that the pain gives rise to, or perhaps fear associated with unfamiliarity of a certain kind of pain, or a new place it is felt in, or the sudden intensity of it, that creates the motivation to pick up the phone? 

..........................

Trying to think back, my earliest recollection of pain: I was a child racing around on somebody's luxurious green lawn with some other children, age 5, at a large gathering of families out in the country, at a big farm, to host a political speaker. I had no prior knowledge that such a beautiful lawn had to be watered every day with underground sprinklers, or that the lawn contained depressions that housed the system. My right foot went into one of these, and I kept going, and I experienced the first truly painful and pain-sustained shock of my earthly existence. 

A howl came out of me that pierced through the entire assembly, I'm sure. Two women came straight over. One was my mother and another, an older lady who said she had nurse's training. My memory of my mother has always been that she had not been competent in containing my pain. She seemed flustered and unsure. Embarrassed. She didn't seem to know what to do. The other lady was kind, took my foot gently, asked me if I could move my toes.. held my foot for a few minutes. She talked gently to my mother, reassured her that I was going to live, that the ankle didn't seem to be broken, that I'd probably be fine. She asked me to stand up and try walking. I could walk, but every step was horrible. The ankle had already begun to swell; even on a child's slim ankle, they seemed not to see it. 

That was it. My mother seemed relieved, and from a few feet away, basically parroted back to me everything I had already heard the lady-who-used-to-be-a-nurse say. I would be alright. It was OK for me to walk around. I could go play again if I wanted to. 

This was not what I had needed from my main caregiver. I would have preferred just then, to have had an affectionate mother, a mom who acted like a bear, who would have ignored the crowd and her social role, who would have shoved all that aside with some sort of roar, who would have swept me into her arms and held me tight and said "there there, it's all going to be OK," no matter what noise I happened to be emitting at the time. But that was never my mom. She always felt exposed, needed to be on her own best behaviour, needed to interact with everyone else, absorbed any helpful psychosocial attention there happened to be available in every/any crisis situation. She couldn't ever produce any of her own child-appropriate psycho-social relational behaviour, not in public at least, and not in private either, that I recall. In public, it was always all about her, even when I was the smallest child. That is our relationship, right there. That is the core of our never-to-ever-be-healed, mother-daughter wound. My entire goal growing up was to never, ever be like her. So I chose to never, ever become an actual mother. I never wanted to inflict that sort of invisible pain on any other people, ever. 

The other lady handled me well, but I could have used a lot more contact for much longer just then. I would like to have had her hold my foot for a good hour, until it really did feel better. It was well and truly sprained. I limped for weeks, enduring the shots of pain that zapped me if I bent the ankle too much, like on stairs, the marble ones outside the hall in Weyburn, where we went as a family to even more political meetings all that fall. My mother never mentioned my ankle, ever again. Eventually the ankle got better on its own. To this day I experience tension in that foot, and it won't plantar flex as easily as does the other or as completely. I've had it treated as an adult, on occasion. I usually keep hidden all the emotional content and neurotags attached to the original injury, keep that separate while having it treated. But my brain can easily pick out who is kind and who isn't, just by how they make contact with my foot and the attached leg.

Such is the price of having a human brain attached to a critter brain in there, and having had a pain experience that wasn't particularly well-handled in the psycho-social sense, according to me. The orbito-frontal cortex is implicated in discernment of emotional aspects of physical contact. 

What did I learn as a small human having an acute pain experience? 

• I learned that the overwhelming nociceptive barrage from an injury to a limb can and will go away eventually, but that dregs can remain in terms of motor output. 
• I learned my mother was kind of useless when it came to being able to look after my sense of self with her sense of self. In all the other ways that mothers are mothers to other humans, she did just fine. But from that day, some little part of me felt like an orphan. Then got used to the feeling. 
• I learned to hate pain. It may have even been then that the seeds were laid for a lifetime of becoming some kind of official pain-buster. I knew it would involve touching and handling and presence. 
• I still hate pain. I learned that lesson very very well. 

I feel, in many ways, at the far end of a life lived peacefully as a human primate social groomer, that I dodged all sorts of bullets that ordinary life offers those whose eyes aren't very wide open. So yes, I feel that pain ripped a hole through previously unconsidered existence, that my brain learned a lot from that pain experience, and with its its own inherent confirmation bias, learned to make lemonade from sour lemons. 

........

The introduction, continued:

"Despite these beneficial aspects of pain, there are negative features that challenge our understanding of the puzzle of pain. What is the benefit of chronic phantom limb pain to an amputee whose stump has healed completely? The pain, not the physical impairment, prevents them from leading a normal life. Likewise, most backaches, headaches, muscle pains, nerve pains, pelvic pains, and facial pains serve no discernible purpose, are resistant to treatment, and are a catastrophe for the people who are afflicted."

Indeed.

I am of the opinion that pain is right there, right at the top of the heap of other useless crap our human brains churn out as symbolic content that has nothing whatever to do with anything.  See Sapolsky.

In my opinion pain is useless persistent human existential angst.

"Pain may be the warning signal that saves the lives of some people, but it destroys the lives of countless others. Chronic pains, clearly, are not a warning to prevent physical injury or disease. They are the disease—the result of neural mechanisms gone awry... In this section, we review past and current theories of pain, including the Neuromatrix theory which suggests brain mechanisms that may underlie some kinds of chronic pain and points to new forms of treatment."

You can say that again.

You can say that again. 

There are problems inherent in classifying chronic pain as a "disease,"  however. The debate rages on. But that is for some future blogpost. 

UPDATE: May 21
Check out the video, Dacher Keltner on Touch, about 8 minutes. Remarkable.

Here are some papers he has been involved in:
Hertenstein MJ, Keltner D, App B, Bulleit BA, Jaskolka AR; Touch communicates distinct emotions. Emotion. 2006 Aug; 6(3):528-33. (abstract)

A list of 65 papers he is involved in. Eight are full text.

Thank you to Tsvetan Vassilev for the find. 

Melzack and Katz, Pain. Part 4: pain is a multidimensional experience across time

The paper, Pain.

Part 1 First two sentences
Part 2 Pain is personal
Part 3a Pain is more than sensation: Backdrop
Part 3b Pain is not receptor stimulation

Part 3c: Pain depends on everything ever experienced by an individual

Here are the next two sentences of the abstract. 

"The neuromatrix theory guides us away from the Cartesian concept of pain as a sensation produced by injury, inflammation, or other tissue pathology and toward the concept of pain as a multidimensional experience produced by multiple influences. These influences range from the existing synaptic architecture of the neuromatrix—which is determined by genetic and sensory factors—to influences from within the body and from other areas in the brain."

Recall that Gifford proposed that the brain was a "stress response coordination center" with outputs out along systems that included a basic four: somatic motor, autonomic including enteric, neuroendocrine and immune. Following evolutionary trails carved deep into scientific terrain, Gifford points out, look: organisms that survive add that survival strategy, all the way from cellular to organismal, to their bank of output behaviour possibility. Maturation at a biological level means a system that has learned lots of ways of coping. Pain is one way of coping... When we treat people, as therapists, we would do well to consider deeper biological meanings of pain as an output. 

Melzack, who did lab research for decades, held burning matches underneath the noses of Scottish terriers reared in isolation and carefully observed their behaviours, finally came up against some kind of internal wall, which forced him to conclude, in four different ways, look: when we view "pain" as something that starts in a body and ends up in a brain, it just doesn't make any sense. That frame is way too simplistic. Here is some evidence, based on studies of paraplegics whose [supposedly!] offending ascending systems were completely silenced, and they still had phantom, body pain, of the most excruciating kind. How do we account for that? How? 

Here's another thing: experience leads a biological organism, like a complex vertebrate mammal creature, to develop "filters" to input from the environment. His dogs didn't develop ordinary filters. Their brains didn't neuroplasticize normally, i.e., didn't develop filters, because the dogs were reared in isolation. As quoted in the book, The Ontogeny of Vertebrate Behavior, Melzack says:

A two-part process in which (a) there is inadequate filtering of inputs on the basis of memories (phase sequences) of the significances of stimuli normally acquired in early experience, so that (b) the total input bombarding the central nervous system produces an excessive central nervous system arousal which, as Hebb (1955a) has suggested, could be responsible for the correspondingly low cue properties necessary for discrimination and adequate responses (1965, pp. 276-277)

Filtering? Filters... hmmn. 

So... really, there might be another layer here. Let's think about this - if a person hasn't had much rough and tumble as a child (like, exposure to dirt, other children, physical contact, e.g., the feeling of body weight through bare feet against cool grass or warm rock or slippery mud puddle or rough gravelly dirt or sharp prairie cactus) their brain won't have learned, perhaps, how to filter out (possibly noxious) physical input in the ordinary context of having simple childish fun. 

Mammal babies all play. Kittens, puppies, bear cubs, baby primates - attack each other (or some convenient parental tail) - bite, scratch, hunt each other, roll all over the ground, over sticks and stones, over embankments, fall off tree limbs.. I submit that mammal children aren't just training their somatic motor output systems - in the context of having psychosocial fun, their other output systems (see Gifford) are being trained up as well. 

What are human children physically exposed to anymore? Is gravel still allowed on playgrounds? 

Probably in most places in the world, children are still allowed to take their own personal lessons from ordinary physical exposure to their environment, hard edges and all. But I do wonder sometimes about the sanitized world of the modern westernized urban parent/child. 

The culture. It comes back to the culture.... sometimes I wonder, could this epidemic of chronic pain have anything to do with this culture having raised us like hot house flowers? 

...............

Here is the final sentence of the abstract - yeah, we made it! To the end of the abstract. Finally. 

"Genetic influences on synaptic architecture may determine—or predispose toward—the development of chronic pain syndromes."

This is the only "bio" factor that has any real meaning, in my own humble opinion. 

Absolutely, if you are a child born without the ability to provide your hungry little brain with any nociceptive experience, it won't be able to learn how to protect you from your environment - your critter brain won't be able to teach you painful lessons. Here is a link to the (misnamed, according to me) CIP page. 
CIP stands for "Congenital Insensitivity to Pain." I think it should be renamed CIN, Congenital Inability to Nocicept. Or else add an S on the end, and call it Congenital Insensitivity to Painful Stimuli. Just to be clear. 
But such children's brains are still primed for learning about and responding to noxious stimuli, still react when they see pain behaviour in others.  See Danziger et al., "Can we share a pain we never felt? Neural Correlates of Empathy in Patients with Congenital Insensitivity to Pain", Neuron (2009), 61(2):203-12. Their critter brains are, at least. Posted to The Girl Who Feels No Pain. 

If CIP is a condition or a group of related conditions, one can imagine a large range of genetic capability or non-capability to transduce nociceptive stimuli, including perhaps, conditions where someone might be born with..
1. way more nociceptive fibres than usual
2. way too many of one kind but not enough of some other kind
3. the usual number and array but they make way too many receptors in response to ordinary stimuli
4. the usual number but don't take down receptors once they've been built
5. the usual number but way too many microglia in the spinal cord that get way too busy 
6. the usual number but not enough interneurons of the right kind at the central terminal
7. some kind of wonky malformed neurotransmitter molecule that doesn't work right or works way too well
8. countless more ways the peripheral and central nervous systems can't quite figure out how to talk to each other harmoniously because of some little genetically produced molecular deficiency or excess or possible epigeneity. 

But maybe everything was genetically set up to be perfect:
Maybe there are developmental windows a normal system has for learning, like the window that exists in a child for learning a second language without an accent, up to age 7 or something. Maybe people miss windows. So maybe there may be the usual number of both nociceptive capable neurons and microglia and everything else in the right proportions, but in a person with a system which never was allowed to build a normal robust response to ordinary environmental physical input.

These are the sorts of things I think about all the time. I know people are working out answers, collecting data, deciphering statistical information, putting out graphs, having conferences, showing each other slides. I know they are trying. My fantasy is that some day everyone will know everything about everything to do with pain. But it won't happen in my lifetime. Of that I am quite certain.  

Melzack and Katz, Pain. Part 3c: Pain depends on everything ever experienced by an individual

The paper, Pain.

Part 1 First two sentences
Part 2 Pain is personal
Part 3a Pain is more than sensation: Backdrop
Part 3b Pain is not receptor stimulation

The next sentence in the abstract is,

"Rather, injury or disease produces neural signals that enter an active nervous system that (in the adult organism) is the substrate of past experience, culture, and a host of other environmental and personal factors."

Please see Part 3b for my personal take on that... but it's not just my opinion..

There is ample support in our profession for the whole idea of a human organism being an accretion of experience through time than just me: Butler. Moseley. Thacker. Gifford. Just a few! Hundreds more. Possibly thousands. Don't everybody all shout at once. 

On second thought, heck - why not? 

Everybody together now!!! What do we want? 

Better pain theory taught at the undergrad level!! 

When do we want it? 

Thirty years ago!! 

.......

In 1998, a remarkable UK PT, Louis Gifford, who subsequently published a remarkable, brilliant series of books on pain, wrote a paper (well, he has written lots of papers, but this one is pivotal in my opinion). Here is the abstract:

Gifford L, Pain, the Tissues and the Nervous System: A conceptual model. Physiotherapy Jan1998, 84:1 27-37

Summary: This paper challenges current clinical models and systems for assessing and managing on-going pain states to incorporate a broader biological and therapeutic framework. Included is an acceptance of the current criticisms made towards a purely tissue based/modality based paradigm for pain treatment. The mature organism model proposed is presented as a workable conceptual starting block for incorporating mechanisms of pain into the broad science of stress biology and the biopsychosocial model of pain.

Gifford's mature organism model (MOM) for PT

In this paper, Gifford wrote that he wanted to help clinicians link together complex issues and mechanisms involved in pain problems, help them see the inadequacy of current approaches, and provide a new pain model. Basically he wanted PTs to start using our brains and get away from ritualistic superficial location-specific modality treatment. He said, "Physiotherapists are being bluntly urged to change their approaches and rationales."

Bluntly! Did we "get it"? Apparently not everybody, and not the schools. Not all at once, and not very evenly. 

He described "the mature organism model (MOM)," which he had taught for many years, in which he argued pain was based on biological stress response. 

"the sensation of pain is seen as a perceptual component of the stress response whose prime adaptive purpose is to alter our behaviour in order to enhance the processes of recovery and chances of survival."

Gifford, with zoology degree from his life before PT, held that the body was gene carrier, and the CNS a "stress response coordination center" that 

"continually samples few innate but vital sample-scrutinise-action (consciously and ‘unconsciously’) the outside environment, its own body and relevant past experiences (the brain samples from ‘itself') - and then ‘outputs’, or responds on what it finds to the best advantage for its body and the vital genes it contains."

Output consisted of behaviour and physiology, expressed through systems:

• somatic motor 
• ANS (sympathetic, parasympathetic, enteric)
• neuroendocrine 
• immune 

Maturation involved learning from successes from behaviours that resulted in surviving. Excellent proposition. I concur completely. 

One could say that pain is a learned behaviour. 

From Melzack and Katz once again, the next sentence of their abstract: 

"These brain processes actively participate in the selection, abstraction, and synthesis of information from the total sensory input."

Yes they do. They certainly do. 
Like learning to ride a bike. Once the brain has learned how to do that, it doesn't forget. There is some sort of implicit learning that goes on in there, about mounting a pain defense. 
.....................

The next sentence:

"Pain is not simply the end product of a linear sensory transmission system; it is a dynamic process that involves continuous interactions among complex ascending and descending systems."

Hmmnn.. I suppose that's the story for most kinds of pain in most people. I'm sure Melzack himself would argue against this statement as being the last word, because as his own research showed, there can be pain of the utmost nasty kind, continuously or intermittently or spontaneously generated in the complete absence of ascending systems altogether, i.e., when previously existing ascending systems became disrupted, even deliberately obliterated. 

I now have obtained and read the paper cited in Part 1 of this series,  Melzack R, Loeser JD. Phantom body pain in paraplegics: evidence for a central ‘‘pattern generating mechanism’’ for pain. Pain 1978, 4:195 – 210. 

Here is the introduction:

"INTRODUCTION
Phantom body pain in paraplegic patients is the most mysterious of all pain phenomena. It has been traditionally assumed [45] that the essential cause of pain in any part of the body is activity in the receptor-fiber units that innervate it. In this paper, however, we shall describe paraplegic patients who had undergone removal of an entire section of the spinal cord (segmental cordectomy) in the attempt to alleviate phantom body pain, yet they still suffered severe pain in the denervated areas of the body. There is no reason to believe that the pain was due to depression or neurosis. Furthermore, the possibility that the pain was produced by nociceptive signals transmitted along the sympathetic chain is ruled out because the pain was not relieved by bilateral sympathetic blocks. The perception of severe, chronic pain in the absence of any input from those parts of the body in which pain is felt has profound implications for theories of pain. The purpose of this paper is to examine the properties of phantom body pains in paraplegics and to propose a theoretical concept to explain them."

My bold. 

This was remarkable, almost 40 years ago, and it's still pretty remarkable today. I mean, think about it. 

The cords were severed, they were not there. The bilateral sympathetic chain as a possible ascending pathway for nociception was not an issue - sympathetic blocks didn't work. 

The paper describes in depth 5 cases, paraplegics who had severe pain of the most excruciating sort, and continued to have pain no matter how much of their ascending pathways were removed. 

This paper was pivotal, in that it provided one of the four "conclusions" or arguments in favour of Melzack moving on from the strictly labelled line, specificity theory of pain, the same track as everyone else was on (and many are still on), and that he'd been on himself, to consider the human brain in pain from the inside out/ top down instead of only from the outside in/bottom up. It has been cited 318 times in the last 35 years.

Melzack and Katz, Pain. Part 3b: Pain is not receptor stimulation

The paper, Pain.


Part 1: Pain. First two sentences
Part 2: Pain is personal
Part 3a: Pain is more than sensation: backdrop

The next sentence in the abstract is,

"Pain processes do not begin with the stimulation of receptors."

Biomedical models of pain
Pain science is generally taught as if it were a short story, with a beginning, middle, and end.

In the beginning were the nociceptors. They were stimulated. The signal went up to the brain. The infant recoiled as its brain registered the input. The child learned to avoid light sockets and stove elements. The child fell, broke his arm, broke her collarbone. It healed easily with no disturbance of function. The person who bore up under ordinary childhood trauma learned to bear up under any sort of adversity, thrived, built a life, died of old age. The person had a normal pain system. At one end of it are nociceptors, and at the other end, death, and in between there are occasional warning bells and maybe operations for this or that, joints that wore out and needed replaced, an appendix that burst while a teen, a couple pregnancies and normal deliveries perhaps.

This is the standard, third person narrative that biomedical researchers use as their frame for "normal." They have to start somewhere, you see. They exist outside of it, and they study pain as if it were a thing, like a bug. Like a noun. They have to pretend it's a thing, because their true quest is to try to figure out how to measure "it," so they can develop ways to fix it.

The problem arises with pain that is outside "normal" - it's hard for them to study whatever exists outside the usual narrative. What's the cause? They look hard for the cause. They are still looking for causes. Which is fine. But a gap exists, where, if there is no apparent cause, pain must be the patient's own fault somehow. 

Biopsychosocial models of pain
Melzack and Katz are saying, no no. Au contraire.
Pain is not a "thing." Pain is a perception. Pain is not a noun, it's a verb.
A person whose nociceptive capable fibres are stimulated, no matter what age, is already a person with a life and a brain and an intrinsic sense of self, whose existential questions will always elude answer, no matter how attractive the hypothesis, or how socially accepted or covered with gilding they may be. [Like the insides of churches in Europe.]
That sense of self will feel itself to have been attacked on some level of its function, and will have learned to cope, or not, depending on how it was raised and what its genetic foundation was to begin with.
Pain is a process that enters into the conscious awareness of an individual, whose brain is already processing everything as perception, according to whatever foundational pathways it has already developed and learned to favour.
That individual was born innocently into a context that preexisted him or her, a context which was, and still is, also a verb, comprised of other individuals, with processing brains that are also more verb than noun. Life moves. Life is the ocean. An individual is a river with mighty currents and undertows. Nociception is a little stream into it, but it's not the ocean, not the river, not the currents. 
Sometimes the context, the family, the cultural container, the relationships, the job opportunities and working relationships, provided the right mix of circumstances and opportunities for a learned, robust resilient response to emerge from that person's brain. Sometimes, it didn't. And doesn't. And won't.
Sometimes the person's own genetic foundation is sufficient to mount a successful resilient and robust response to a pain perception in spite of the random circumstances of birth and life. Sometimes it isn't. Sometimes the individual has the means and options available, in the moment, to consciously choose an action that will decrease or eliminate his or her pain. Sometimes, he or she does not.

My take
As humans, we end up embedded into a context of cobbled up social, cultural, familial and community ties and obligations. Our illusion usually is that we have chosen our lives. The truth is that usually our psychosocial lives have chosen us, and we either blithely, or numbly, or in some combination, follow the traces of a culture we're born into, speak its language, follow its mores, adhere to its morals (or at least try to), pray to its god or gods, and die upon its bosom.
Melzack and Katz are aware of all this, and how shaped we all are by all of it. They're saying, look, it's not the pain patient's fault they have chronic pain. Life is an ongoing dance between an individual and the forces which have shaped that individual and the pulls and tugs upon that individual by everyone with whom they are connected, not only their biology, not only the genetic array they were born with. It's called "life," and it has the beginning, middle and end. And every life has a context - every individual has a psychosocial environment that preceded, and will outlast, her or him, and with which that individual must interact. Yes, yes, we know we can't "treat" the whole frickin' culture, but let's at least factor it into the picture. Let's make a new, more realistic model that includes it all! 

Let's teach them a little bit about water cycles..

That way, when a person comes to us with pain that won't go away, we can use this model that doesn't objectify them or refuse to acknowledge them as subject in the midst of their own life. Life is interaction. You know that's true. It's true even at the fundamental, biological level. So, c'mon people: We can't treat people as though they were identical objects. Or bugs. At least not when they're awake and trying to understand why they have pain. We have to have a pain model to use when we interact with live, awake people, so we can help them begin to understand that not only is their pain not their fault, but that it isn't anyone else's fault either, particularly;  a model that helps them see that they have a sense of self, illusion though that may be, and that it has considerable leverage in there. That they might place their sense of self in various domains, consider their own existence from various perspectives. That they might begin to unravel the tangle within that they may have never even known existed. That they do have a locus of control. That they can begin to move again, maybe only their perspective, at first; then, maybe, eventually, physically too. A perspective that they possess, and must embrace, and learn to wield. 

Melzack and Katz, Pain. Part 3a: Pain is more than sensation; backdrop

Art by Sigurd Mikkelsen of Norway, used with permission

Part 1
Part 2
The paper, Pain.

Unpacking this may take awhile. There are four sentences here, beautifully illustrated by Sigurd Mikkelsen, a PT in Norway. 

Before we discuss the words (see future posts), please bear with me as I just look at the image, and let it sink in for a little while, let my mind (once upon a time steeped in the study of art) meander some more. 

A few points must be made, according to me at least...  Chief among them is this: Art is symbolic. It's not real. See Sapolsky. 

Note the natural setting, the isolated tree, the ground swelling up, the sky radiating down. This poetic image has deeper psychosocial implications, and I want to highlight a few reality checks for us to bear in mind. 

The natural setting
We like to look at nature, especially when it's safely inside a harmless image, and pretend we are not part of it. Actually going out into, being out in nature, is something that our brains are excited by, made nervous by. 

• Usually we drag a lot of expensive equipment and food out with us, and go with other people, assuage our nervousness with a psychological safety blanket. [Myself, I'm a bit paranoid about bears.]
• We drag elements of nature inside our human world and habitat, so we might enjoy them, in safety. These are known as "zoos" and "parks." 
• We make plastic replicas of palm trees and flowers, and decorate our winters with artificial lights
• We invented religion so we could escape from the illusion of being marooned on some planet, enduring a life sentence, into a secondary illusion of being rescued from it somehow, sprung from jail, into some eternal wonderland where all our needs and wants are forever fulfilled and all the questions answered - and do eternal life. [Personally, I'm OK with just 'doing time', right here, until I can go back to being the way I was before I was ever conceived.]

The single isolated tree 
The tree represents life. The isolation of it evokes, but in a safe, contained way, the sense of isolation each of us feels as we move through life, an illusion of uniqueness or sense of self. 

A unique sense of self is a brain illusion - but the feeling is very real. To complicate things, to a primate, there is an inherent scariness in the feeling of isolation. 

A sense of isolation is itself an illusion: it's tied to the [necessary!] illusion of a unique sense of self. 

The absolute conundrum this poses, the unsolvability of this inherent contradiction, drives us to cherish family ties and seek friends, seek helpers, seek grooming, a throwback to our inherent primate troop origins. See Dunbar. 
To get around this and feel secure, I like to remind myself:

• Nature is a verb, not a noun: my particular life is just part of it, not apart from it
• I am made of the same kinds of living cells that everyone else is
• the whole biosphere is made of living cells; multi-celled organisms evolved from single celled ancestors. See Lynn Margulis. 
• my body's cells are only one-tenth "me" (with unique "me" DNA in them) and 9-tenths other, the microbiome
• the conglomeration of living cells that holds itself together, in something we can identify as "self," is temporary, but life itself persists, driven by rather mysterious and counterintuitive thermodynamic processes possibly unique to our planet (possibly not, as life may exist elsewhere in the universe as well)
• I can relax, knowing the planet and the world will continue on just fine without "me" having to be in it, some day. 

The ground 
It undulates, seems to lift itself up toward the sky slightly, representing the yearning we may feel to escape our "ground," our "earth," our "body," our "mortal coil." Well, that will never happen, because no matter where you go, there you are, in a body. On the planet. Unless you can go to the space station for awhile. Until that body [inevitably] lets go of its coherence, or its cells do, and we die. 

The sky 
It radiates down on the tree, sun rays giving light energy to the tree, so life may flourish. 


So, that's the backdrop, a fitting one! to the sentences by Melzack emblazoned over it. Which is where we will go next. 

Melzack & Katz Pain2013 Part 2: Pain is personal

The paper, Pain.

Part 1 of this adventure meandering through it. 

Yesterday we made it through the first two sentences of the abstract. [Which was a classic example of how meandering my mind is. Like a stream on the prairie. It goes anywhere it can, always very slowly, because there isn't much of a gradient in there.]

Anyway, today we continue. Third sentence of the abstract:

"Pain is a personal, subjective experience influenced by cultural learning, the meaning of the situation, attention, and other psychological variables."

The example that comes to mind in just the last couple months, is Kevin Ware. [graphic warning]
So, this guy's leg crumples as he lands on it, something he's done thousands of times, probably, only this time, for some weird reason, his tibia, one of the strongest freakin' bones in the whole body, breaks on landing, and he falls over. Here is a video. [graphic warning]

Several teammates crumple too. It's like they are part of a superorganism. Maybe they are. A symbolic superorganism called a team. Maybe it's just mirror neurons. 

Kevin Ware certainly looks like he had pain at the time - his face contorts for a few seconds. But he is conscious, remains calm, tells his teammates to get back out there and win, doesn't faint or throw up. Later he declares he didn't feel any pain, was just surprised by the episode. 

"I saw the bone six inches out ... I didn't feel any pain. It didn't hurt. Honestly, it didn't hurt. It was just scary. It was probably one of the scariest moments in my life." 

His face looked more like it expressed pain than fear, though. Just for a few seconds. He likely did experience some nociceptive input, which enters S1into BA3a, according to Smith, from projection neurons associated with the spinothalamic tract [along with proprioceptive input from muscle spindle receptors via ventroposterior superior nucleus..]. A deltas are pretty swift - they are myelinated nociceptive fibres that must end up somewhere,  although the only information I've been able to glean about nociception and S1 has been about C's. My guess is, they probably are processed and their stimulus intensity recorded by the other three areas that process mechanoreception intensity from skin. 

4 Brodmann areas are associated with S1 cortex

BA3a handles proprioceptive, and SOME nociceptive input. The other three areas handle cutaneous mechanoreceptive input. 

S1 doesn't do anything but record intensity of a stimulus. It doesn't entertain any opinion on what the stimulus might mean. It just ... objectively records intensity. [See Smith, and the blogpost on David Seminowicz for more about that, and a list of references.] If the prefrontals are working hard, i.e., if there is a threat situation going on and adrenaline is pumping and the prefrontals are soaked in noradrenalin from locus ceruleus, they'll be able to kick in that whole descending modulation business in a favorable way. 

But... what did Kevin Ware do with his prefrontals when he experienced a burst of nociception somatotopically represented in the dorsolateral periaqueductal grey? He stayed level - he didn't conclude [..or rather, his brain didn't decide] that he must be dying, then try engage his own possum reflex through the ventrolateral part of periaqueductal grey - he/his brain didn't want to deploy opioids - he was up for a fight because he's just been playing basketball, he was on the floor with an injury, he realized he couldn't get back up so there wasn't much around to fight with anymore except his own nociceptive input, and I bet he decided to fight with that instead. Not a conscious decision, just his brain deciding for him, based on the circumstances and whatever was racing through it, anyway, in terms of neurochemistry. 

So, good for him. 

...... 

June 3/13: Update: Video, depicting Ramon Ortiz of the Toronto Blue Jays reacting to an elbow injury sustained while pitching a baseball game, his pain behaviour as he experienced his own injury: Compare the two events. In Ware's case the injury was outrageously visible, and the teammates and crowd did a lot of reacting. In Ortiz' case, it's a closed injury. Psychosocial context and outward behaviour is different.
Who do you think might carry a more entrenched pain neurotag in the future? 

Melzack's and Katz' new paper; Pain. Part 1. (First two sentences of the abstract)

Yes, it's called, simply, Pain. By Ronald Melzack, (see biography) and Joel Katz.

Wiley Interdisciplinary Reviews: Cognitive Science Volume 4, Issue 1, pages 1–15, January/February 2013

Full text !

I love this paper. I'm planning to deliciously and slowly devour every morsel of it, maybe taking several blogposts to do so, and report every flavour I find. Because I want to sink myself deep into this recent writing, lose myself, wander around inside his mind.

................ 

Here is the abstract:

"Pain has many valuable functions. It often signals injury or disease, generates a wide range of adaptive behaviors, and promotes healing through rest. Despite these beneficial aspects of pain, there are negative features that challenge our understanding of the puzzle of pain, including persistent phantom limb pain after amputation or total spinal cord transection. Pain is a personal, subjective experience influenced by cultural learning, the meaning of the situation, attention, and other psychological variables. Pain processes do not begin with the stimulation of receptors. Rather, injury or disease produces neural signals that enter an active nervous system that (in the adult organism) is the substrate of past experience, culture, and a host of other environmental and personal factors. These brain processes actively participate in the selection, abstraction, and synthesis of information from the total sensory input. Pain is not simply the end product of a linear sensory transmission system; it is a dynamic process that involves continuous interactions among complex ascending and descending systems. The neuromatrix theory guides us away from the Cartesian concept of pain as a sensation produced by injury, inflammation, or other tissue pathology and toward the concept of pain as a multidimensional experience produced by multiple influences. These influences range from the existing synaptic architecture of the neuromatrix—which is determined by genetic and sensory factors—to influences from within the body and from other areas in the brain. Genetic influences on synaptic architecture may determine—or predispose toward—the development of chronic pain syndromes."

OK, so even this much, the abstract only, contains depths I have yet to plumb. 

"Pain has many valuable functions. It often signals injury or disease, generates a wide range of adaptive behaviors, and promotes healing through rest."

1. "Chest pain may be a symptom of heart disease."

 It might make us go to the doctor. I should hope so. Any unusual pain anywhere in the trunk, especially in the front of the trunk, anywhere from top to bottom, would certainly drive me to pick up the phone to the doctor's office, or call an ambulance. Absolutely. Pain compels. 

2. "Memories of past pain and suffering also serve as signals for us to avoid potentially dangerous situations." I should think so! If you remembered falling down the front steps carrying a bag of groceries 20 years ago, breaking your ankle, chances are pretty high your brain would remember "steps=danger" every time you went to tackle some, especially carrying groceries, or anything. You might not be the first to volunteer to help a friend move. 

3. Pain makes us rest. Yes. If you don't move around for awhile freely, because the spinal cord/brainstem/critter brain takes over and stops motor output from happening fluidly, makes us have to figure out ways of guarding our bodies by giving us pain, the tissues will heal better, or so we think, except for when the time frame stretches out way beyond the length of time it usually takes for tissue to glue itself back together. Three months, and that's being generous. Even bone can knit (not be strong, but at least knit) by about 6-8 weeks. 

.....

"Despite these beneficial aspects of pain, there are negative features that challenge our understanding of the puzzle of pain, including persistent phantom limb pain after amputation or total spinal cord transection."

1. Phantom limb pain, not the physical impairment, stops people from leading a normal life.

"Likewise, most backaches, headaches, muscle pains, nerve pains, pelvic pains, and facial pains serve no discernible purpose, are resistant to treatment, and are a catastrophe for the people who are afflicted." (page1)  On some level, yes they are. Yes pain is.

2. "Pain might be a warning signal that saves the lives of some people, but it destroys the lives of countless others." I guess that's assuming we want to be here in the first place, we feel embedded, and that life isn't just a piece of corn. 

3. Chronic pains are not preventive warning - they are the result of neural mechanisms gone awry.

Here are the first three references to support this statement:

1. Niv D, Devor M. Chronic pain as a disease in its own right. Pain Pract 2004, 4:179–181. (no abstract available) 

2. Siddall PJ, Cousins MJ. Persistent pain as a disease entity: implications for clinical management. Anest Anal 2004, 99:510–520. (full text) 

3. Woolf CJ. Pain: moving from symptom control toward mechanism-specific pharmacologic management. Ann Intern Med 2004, 140:441–451. (abstract only)

Skip to page 3:

 "In 1978, Melzack and Loeser described severe pains in the phantom body of paraplegic patients with verified total sections of the spinal cord, and proposed a central ‘pattern generating mechanism’ above the level of the section. This concept represented a revolutionary advance: it did not merely extend the gate; it said that pain could be generated by brain mechanisms in paraplegic patients in the absence of a spinal gate because the brain is completely disconnected from the cord. Psychophysical specificity, in such a concept, makes no sense; instead we must explore how patterns of nerve impulses generated in the brain can give rise to somesthetic experience."

Here is the reference: 17. Melzack R, Loeser JD. Phantom body pain in paraplegics: evidence for a central ‘‘pattern generating mechanism’’ for pain. Pain 1978, 4:195 – 210. (abstract only)

"Examines the proposition that chronic pain may be caused by a loss of sensory input. Cases in the earlier literature are reviewed, and new cases are presented of chronic pain patients who sustained total spinal cord sections. The completeness of the lesion was verified visually during surgical removal of injured tissue or as a result of segmental cordectomy to prevent nerve impulses produced by injured tissues from reaching the brain. Nevertheless, pain returned immediately or as long as 11 yrs later. The pain was usually felt in definite parts of the phantom body and was often described as burning, crushing, or cramping. The sympathetic ganglia—the only other possible route for nerve impulses from the legs—were also blocked in several patients without effect on the pain. There is convincing physiological evidence to show that deafferentation produces abnormal physiological activity in spinal and brain cells deprived of input. The cells fire spontaneously in high frequency bursts and may be triggered by inputs from adjacent structures; the abnormal firing may persist for hours after a single, brief triggering stimulus, and abnormal activity has been observed to persist for months. A model is presented which proposes that synaptic areas along the transmission routes of the major sensory projection systems, from the dorsal horns to the somatosensory projection areas in the thalamus and cortex, may become pattern generating mechanisms. (45 ref) (PsycINFO Database Record (c) 2012 APA, all rights reserved)"

This is a delicious, although tiny, little crumb. Cited by 318 since 1978 -  I can't access the paper itself. Seems like few pain investigators are interested in delving into pain that doesn't have a spinal cord with intact pathways attached. Yet, here we are. Edge of a cliff. Dang. 

Melzack stands by this paper. 

A bit further on, page 4, this: 

"the data on painful phantoms below the level of total spinal cord section, indicate that we need to go above the spinal cord and into the brain."

References: 

18. Melzack R. Phantom limbs and the concept of neuromatrix. Trend Neurosci 1990, 13:88 – 92. (abstract only, 513 citations)"The phenomenon of a phantom limb is a common experience after a limb has been amputated or its sensory roots have been destroyed. A complete break of the spinal cord also often leads to a phantom body below the level of the break. Furthermore, a phantom of the breast, the penis, or of other innervated body parts is reported after surgical removal of the structure. A substantial number of children who are born without a limb feel a phantom of the missing part, suggesting that the neural network, or ‘neuromatrix’, that subserves body sensation has a genetically determined substrate that is modified by sensory experience." 

19. Melzack R. Phantom limbs, the self, and the brain (The D.O. Hebb memorial lecture). Canad Psychol 1989, 30:1 – 16. (abstract only, 182 citations)"An examination of phantom limb phenomena has led to 4 conclusions: The experience of a phantom limb has the quality of reality because it is produced by the same brain processes that underlie the experience of the body when it is intact; neural networks in the brain generate all the qualities of experience that are felt to originate in the body; the experience of the body has a unitary, integrated quality that includes the quality of the "self"; and the neural network that underlies the experience of the body-self is genetically determined but can be modified by sensory experience. A theory is developed to explain these conclusions. It is proposed that we are born with a widespread neural network (the "neuromatrix") for the body-self, which is subsequently modified by experience. The neuromatrix imparts a pattern on all inputs from the body, so that experiences of one's own body have a quality of self and are imbued with affective tone and cognitive meaning."

THE FOUR CONCLUSIONS

These are: (page 4)

1. Phantom limbs feel so... real!

"First, because the phantom limb feels so real, it is reasonable to conclude that the body we normally feel is subserved by the same neural processes in the brain as the phantom; these brain processes are normally activated and modulated by inputs from the body but they can act in the absence of any inputs."

Even people without amputations can feel phantom limbs. It's become a bit of a parlour trick, even. Rubber hand illusions, etc., are being thoroughly investigated.  Even illusions that simply distort the visual perception of an arthritic hand, moving, lengthening, can help reduce pain that feels as though it comes from the hand. Is the pain coming from the real hand? Or from the "virtual" hand stored in a person's sense of self, or neuromatrix? 

2. Sensations, including the sensation of "pain", all the "qualities of experience" we feel from being in a body, can all be "felt" without any inputs from the body. 

"Second, all the qualities of experience we normally feel from the body, including pain, are also felt in the absence of inputs from the body; from this we may conclude that the origins of the patterns of experience lie in neural networks in the brain; stimuli may trigger the patterns but do not produce them."

References for this derive from the phantom limb studies listed above, and this one: 

21. Melzack R. Pain and the neuromatrix in the brain. J Dental Ed 2001, 65:1378–1382. Full access. 

But, also see Slater et al,  Inducing Illusory Ownership of a Virtual Body, Front Neurosci. 2009 September; 3(2): 214–220. (full access.)  

Sense of self was dislocated onto a mannequin, which was then threatened with a hammer; the subjects (the critter brain at least, anterior cingulate and insula) reacted  as though their own body was being threatened.

3. Human "Self"'s feel isolated from the rest, from others. 

"Third, the body is perceived as a unity and is identified as the ‘self’, distinct from other people and the surrounding world." 

Each human feels him or her "self" to be a vulnerable target, sticking out into space, center of the universe or something. This isn't entirely narcissistic, it's likely neurological. It likely drives us to be more social. To compensate we try to "blend in", not be a purple cow, because there is a primate instinct in there, to be part of a troop and stay safe. 

4. The "Self" is still inside a physicality, however, one that emerged.

"Fourth, the brain processes that underlie the body-self are ‘built-in’ by genetic specification, although this built-in substrate must, of course, be modified by experience, including social learning and cultural influences." 

You can't really exist (continue to emerge) without a physical substrate. It just doesn't work. 

 .....

So, here we are - I've sat and worked on fathoming this for hours, deliciously, and I'm still only two sentences into the abstract. This is turning into a total fugue. And I enjoy fugue. 

I intend to digest every word of this paper, in this deliberately repetitive and building fashion.