Is pain where you feel it in the body, or in the brain? Neurophenomenology and the spatial aspect of nociception

Pain is interesting, salient, mysterious. It may feel like it is in one specific place in or on the body. It may feel diffuse, with gradations, or it may seem referred from one area to another. What is happening in the brain and in the body as these spatial aspects of pain are experienced? How much of the causation of pain occurs where we feel it, and how much occurs in the brain? Below is a series of probes and thinking aloud about where pain is, with speculations to stimulate my thinking and yours.  I’m not a “pain expert”, nor a bodyworker that heals clients, nor a physiologist with a specialization in nociception, but a cognitive scientist, with clinical psychology training, interested in body phenomenology and the brain.  Please do post this essay to Facebook, share it, critique, respond, and comment (and it would be helpful to know if your background is in philosophy, neuroscience, bodywork, psychology, medicine, a student wanting to enter one of these or another field, etc). Pain should be looked at from multiple angles, with theoretical problems emphasized alongside clinical praxis, and with reductionistic accounts from neurophysiology juxtaposed against descriptions of the embodied phenomenology and existential structures.  As I have mentioned elsewhere, it is still early in the history of neurophenomenology…let a thousand flowers bloom when looking at pain. We need data, observations, insights and theories from both the experience side as well as the brain side. Francisco Varela aptly described how phenomenology and cognitive neuroscience should relate:

“The key point here is that by emphasizing a codetermination of both accounts one can explore the bridges, challenges, insights, and contradications between them. Both domains of phenomena have equal status in demanding full attention and respect for their specificity.”

We all know what pain is phenomenologically, what it feels like, but how to define it? The International Association for the Study of Pain offers this definition: “an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage.” Of particular interest to neurophenomenology and embodied cognitive science is their claim that “activity induced in the nociceptors and nociceptive pathways by a noxious stimulus is not pain, which is always a psychological state.” Good that they do not try to reduce the experience of pain to the strictly physiological dimension, but I wonder how Merleau-Ponty, with his non-dualistic ontology of the flesh would have responded. Pain seems to transgress the border of mind and body categories, does it not? I am slowly biting off chucks of the work on pain at the Stanford Encyclopedia of Philosophy. Lots of provocative angles, including this one:

“there appear to be reasons both for thinking that pains (along with other similar bodily sensations) are physical objects or conditions that we perceive in body parts, and for thinking that they are not. This paradox is one of the main reasons why philosophers are especially interested in pain.”

Right now I am particularly interested in the spatial aspect of where pain seems to be, what I might label the spatial phenomenology of nociception. When I introspect on aching parts of my feet, it seems as if the pain occupies a volume of space. Using manual pressure I can find places on my feel that are not sore, right next to areas that are slightly sore, which are in turn near focal areas of highest pain. It seems as if the pain is locatable “down there” in my body, and yet what we know about the nociceptive neural networks suggests the phenomenology is produced by complex interactions between flesh, nearby peripheral nerves, the central nervous system, and neurodynamics in the latter especially. A way of probing this this would be to examine the idea that the pain experience is the experiential correlate of bodily harm, a sort of map relating sensations to a corresponding nerve activated by damage to tissue. So, is the place in my body where I feel pain just the same as where the damage or strain is? Or, Is pain caused by pain-receptive nerves registering what is happening around them, via hormonal and electrical signals? Or is pain actually the nerve itself being “trapped” or damaged, yet in a volume of undamaged tissue one can feel hurts? Could the seeming volume of experienced pain-space be a partial illusion, produced by cognizing the tissue damage as some place near or overlapping with yet not spatially identical to where the “actual” damage is, in other words a case of existential-physiological discrepancy? One scenario could be, roughly, that pain “is” or “is made of” nerves getting signals about damage to tissue; another would be that pain “is” the nerves themselves being damaged or sustaining stress or injury. Maybe pain involves both? Maybe some pain is one, or the other? In terms of remembering how my heel pain started, it’s not so easy, but I love to walk an hour or two a day, and have done so for many years. I recall more than ten years ago playing football in the park, wearing what must have been the wrong sort of shoes, and upon waking the next day, having pretty serious pain in my heel. Here are some graphics that, intuitively, seem to map on to the areas where I perceive the pain to be most focal:

from bestfootdoc.com

from setup.tristatehand.com

from plantar-fasciitis-elrofeet.com

If I palpate my heel, I become aware of a phenomenologically complex, rich blend of pleasure and pain. I crave the sensation of pressure there, but it can be an endurance test when it happens. Does the sensation of pressure that I want reflect some body knowledge, some intuitive sense of what intervention will help my body heal? How could this be verified or falsified? It is not easy to describe the raw qualia of pain, actually. I can describe it as achey and moderately distressing when I walk around, and sharp upon palpating. Direct and forceful pressure on the heel area will make me wince, catch my breath, want to gasp or make sounds of pain/pleasure, and in general puts me in a state of heightened activation. But I love it when I can get a therapist to squeeze on it, producing what I call “pain-pleasure”:

from indyheelpaincenter.com

This diagram below helps me map the sensations to the neuroanatomy. We need to do more of this sort of thing. This kind of representation seems to me a new area for clinical neurophenomenological research (indeed, clinical neurophenomenology in general needs much more work, searching for those terms just leads back to my site, but see the Case History section in Sean Gallagher’s How the Body Shapes the Mind).

from reconstructivefootcaredoc.com

What is producing the pain-qualia, the particular feeling? Without going too far into varying differential diagnosis, it is commonly attributed to plantar fasciitis.  There the pain would be due to nociceptive nerve fibers activated by damage to the tough, fibrous fascia that attach to the calcaneus (heel bone) being strained, or sustaining small ripped areas, and/or local nerves being compressed or trapped. A 2012 article in Lower Extremity Review states that “evidence suggests plantar fasciitis is a noninflammatory degenerative condition in the plantar fascia caused by repetitive microtears at the medial tubercle of the calcaneus.” There are quite a few opinions out there about the role of bony calcium buildups, strain from leg muscles, specific trapped nerves and so forth, and it would be interesting to find out how different aspects of reported pain qualia map on to these. Below you can see the sheetlike fascia fiber, the posterior tibial nerve, and it’s branches that enable local sensations:

from aafp.org

Next: fascia and the innervation of the heel, from below:

from mollyjudge.com

Another view of the heel and innervation:

from mollyjudge.com

Below is a representation of the fascia under the skin:

from drwolgin.com

There is a very graphic,under the skin, maybe not SFW surgeon’s-eye perspective on these structures available here. Heel pain turns out to be very common, and is evidently one of the most frequently reported medical issues. Searching online for heel pain mapping brings up a representation purportedly of 2666 patients describing where they feel heel pain: I can’t find where this comes from originally and can’t speak to the methodology, rigor, or quality of the study, but the supposed data are interesting, as is the implicit idea of spatial qualia mapping:  the correspondence of experienced pain to a volume of space in the body. It also quite well represents where the pain is that I feel. The focal area seems to be where the fascia fibers attach to the calcaneus, an area that bears alot of weight, does alot of work, and is prone to overuse. So, where is the pain? Is it in the heel or the brain? Is it in the tissue, the nerve, or both? Is there a volume of flesh that contains the pain? I am going to have to think about these more, and welcome your input. What about the central nervous system that processes nociceptive afferents coming from the body? A good model of pain neurophenomenology should involve a number of cortical and subcortical areas that comprise the nociceptive neural network: -primary somatosensory cortex (S1) and secondary somatosensory cortex (S2): -insula -anterior cingulate cortex (ACC) -prefrontal cortex (PFC) -thalamus Here are some representations of the pain pathways, or the nociceptive neural network:

from Moisset and Bouhassira (2007)

Moisett el (2009)

 

from Tracey and Mantyh (2012)

Broadly speaking, pain seems to be generated by tissue damage, inflammation, compromising the integrity of tissue, stress on localized regions, and so forth being processed by peripheral afferent pain pathways in the body, then phylogenetically ancient subcortical structures, and then the aforementioned cortical regions or nociceptive neural network.  As I have mentioned many times, making a robust account of how various regions of the brain communicate such that a person experiences qualia or sensory phenomenology will need to reference neurodynamics, which integrates ideas from the physics of self-organization, complexity, chaos and non-linear dynamics into biology.  It is gradually becoming apparent to many if not most workers in the cognitive neurosciences that there are a host of mechanisms regions of the brain use to send signals, and many of these are as time dependent as space dependent. Michael Cohen puts it thusly: “The way we as cognitive neuroscientists typically link dynamics of the brain to dynamics of behavior is by correlating increases or decreases of some measure of brain activity with the cognitive or emotional state we hope the subject is experiencing at the time. The primary dependent measure in the majority of these studies is whether the average amount of activity – measured through spiking, event-related-potential or -field component amplitude, blood flow response, light scatter, etc. – in a region of the brain goes up or down. In this approach, the aim is to reduce this complex and enigmatic neural information processing system to two dimensions: Space and activation (up/down). The implicit assumption is that cognitive processes can be localized to specific regions of the brain, can be measured by an increase in average activity levels, and in different experimental conditions, either operate or do not. It is naïve to think that these two dimensions are sufficient for characterizing neurocognitive function. The range and flexibility of cognitive, emotional, perceptual, and other mental processes is huge, and the scale of typical functional localization claims – on the order of several cubic centimeters – is large compared to the number of cells with unique physiological, neurochemical, morphological, and connectional properties contained in each MRI voxel. Further, there are no one-to-one mappings between cognitive processes and brain regions: Different cognitive processes can activate the same brain region, and activation of several brain regions can be associated with single cognitive processes. In the analogy of Plato’s cave, our current approach to understanding the biological foundations of cognition is like looking at shadows cast on a region of the wall of the cave without observing how they change dynamically over time.” But what of the original question? Is pain where you feel it in the body, or in the brain? It seems to me the answer must be both.  The experience of pain being localized there or a little on the left is a product of local tissue signals and receptor activation, which produces peripheral afferent nerve firing, which gets processed by spinal afferent neurodynamics, brainstem activation, thalamic gating, and then somatosensory, insular, anterior cingulated, and prefrontal cortical regions. Yet the real model of pain, one that invokes mechanisms and causes, remains elusive. And a good model of pain must account for the possibility of pain without suffering as well! For now, what I can offer are probes to get us speculating, thinking critically, and eventually building a clinical neurophenomenology of pain. If that interests you, by all means get involved.

An excerpt from the foundational text of neurophenomenology: Varela, Thompson, and Rosch’s The Embodied Mind

It is very,very gratifying to see interest in neurophenomenology increasing. Welcome! Exciting things are happening. If you feel like you could make a contribution to the field, do it! We are still in the early phase, though probably at the “end of the beginning”. In 1996 you could find about three references online (in mid 2013, Google shows 35,400 results). Around then I got a copy of neurophenomenologist/cognitive scientist Francisco Varela, philosopher Evan Thompson, and cognitive psychologist Eleanor Rosch’s The Embodied Mind: Cognitive Science and Human Experience. To this day I am struck by the lucidity of the writing, the patient willingness to explore the virtues of opposing viewpoints, and especially the depth of the challenge to mainstream cognitive neuroscience and psychology. The basic idea is that the science of cognition and the brain needs to somehow reckon with human experience, in all it’s phenomenological, fleshy, ecologically situated complexity. The science of human cognition requires an account of how life seems to us, how it feels, what it means. Not doing so amounts to a shortcut, though an understandable one, given the difficulties routinely encountered. The authors painstakingly present the case for why failing to include the role of the evolutionarily developed phenomenological body and the meaningful, experiential, existential dimensions will hamper scientific accounts of cognition and the brain. Varela, Thompson and Rosch present a radical challenge to the idea that the mind is best modeled based on data and measurements only from the outside, or purely objectively. Cognitive neuroscience describes cognition and consciousness as machinery emerging from the hardware of the brain, and Varela, Thompson and Rosch carefully explore the benefits of this view, but opt for a radical alternative. I am convinced it is the foundational and definitive work in neurophenomenology. Interestingly, Daniel Dennett, a staunch defender of cognitivist orthodoxy, had substantive criticism but went on to say: “the authors find many new ways of putting together old points that we knew were true but didn’t know what to do with, and that in itself is a major contribution to our understanding of cognitive science.” The term “neurophenomenology” does not appear in this book. As I have mentioned elsewhere, the term emerges around 1990 from the work of Charles Laughlin (though there seems to be one mention in a hard-to-find publication from 1988). I had considered directly contacting Varela around 1996 to convince him of the helpfulness of the term “neurophenomenology”, and I must admit to an utter dopamine blast of pleasure when around that time I found his 1996 paper “Neurophenomenology : A Methodological Remedy for the Hard Problem“. Kismet! It was an exciting time, and helped push me towards doing a PhD on one narrow aspect of clinical neurophenomenology: modeling how accurate patients are at reporting on their cardiac rhythm states, and how the brain both enables knowledge and mistaken beliefs about heartbeats . With new people showing an interest in and perhaps coming into this field, we might as well make sure to examine the core text: The Embodied Mind. There is a copy online and here is an excerpt, but I highly recommend getting a physical copy. Here is a section entitled The Retreat into Natural Selection, from Chapter 8: Enaction: Embodied Cognition (for what it’s worth, in my last class as a PhD student, I had my colleagues in David Buss‘ Evolutionary Psychology seminar read and discuss this chapter, and they hated it!) . “In preparation for the next chapter, we now wish to take note of a prevalent view within cognitive science, one which constitutes a challenge to the view of cognition that we have presented so far. Consider, then, the following response to our discussion: “I am willing to grant that you have shown that cognition is not simply a matter of representation but depends on our embodied capacities for action. I am also willing to grant that both our perception and categorization of, say, color, are inseparable from our perceptually guided activity and that they are enacted by our history of structural coupling. Nevertheless, this history is not the result of just any pattern of coupling; it is largely the result of biological evolution and its mechanism of natural selection. Therefore our perception and cognition have survival value, and so they must provide us with some more or less optimal fit to the world. Thus, to use color once more as an example, it is this optimal fit between us and the world that explains why we see the colors we do.” We do not mean to attribute this view to any particular theory within cognitive science. On the contrary, this view can be found virtually anywhere within the field: in vision research, it is common both to the computational theory of Marr and Poggio and to the “direct theory” of J. J. Gibson and his followers.  It is prevalent in virtually every aspect of the philosophical project of “naturalized epistemology.”  It is even voiced by those who insist on an embodied and experientialist approach to cognition. For this reason, this view can be said to constitute the “received view” within cognitive science of the evolutionary basis for cognition. We cannot ignore, then, this retreat into natural selection. Let us begin, once again, with our now familiar case study of color. The cooperative neuronal operations underlying our perception of color have resulted from the long biological evolution of the primate group. As we have seen, these operations partly determine the basic color categories that are common to all humans. The prevalence of these categories might lead us to suppose that they are optimal in some evolutionary sense, even though they do not reflect some pregiven world. This conclusion, however, would be considerably unwarranted. We can safely conclude that since our biological lineage has continued, our color categories are viable or effective. Other species, however, have evolved different perceived worlds of color on the basis of different cooperative neuronal operations. Indeed, it is fair to say that the neuronal processes underlying human color perception are rather peculiar to the primate group. Most vertebrates (fishes, amphibians, and birds) have quite different and intricate color vision mechanisms. Insects have evolved radically different constitutions associated with their compound eyes. One of the most interesting ways to pursue this comparative investigation is through a comparison of the dimensionalities of color vision. Our color vision is trichromatic: as we have seen, our visual system comprises three types of photoreceptors cross-connected to three color channels. Therefore, three dimensions are needed to represent our color vision, that is, the kinds of color distinctions that we can make. Trichromacy is certainly not unique to humans; indeed, it would appear that virtually every animal class contains some species with trichromatic vision. More interesting, however, is that some animals are dichromats, others are tetrachromats, and some may even be pentachromats. (Dichromats include squirrels, rabbits, tree shrews, some fishes, possibly cats, and some New World monkeys; tetrachromats include fishes that live close to the surface of the water like goldfish, and diurnal birds like the pigeon and the duck; diurnal birds may even be pentachromats).  Whereas two dimensions are needed to represent dichromatic vision, four are needed for tetrachromatic vision (see figure 8.6), and five for pentachromatic vision. Particularly interesting are tetrachromatic (perhaps pentachromatic) birds, for their underlying neuronal operations appear to differ dramatically from ours.

 

Figure 8.6 Tetrachromatic vs. trichomatic mechanisms are illustrated here on the basis of the different retinal pigments present in various animals. From Neumeyer, Das Farbensehen des Goldfisches. When people hear of this evidence for tetrachromacy, they respond by asking, ”What are the other colors that these animals see?” This question is understandable but naive if it is taken to suggest that tetrachromats are simply better at seeing the colors we see. It must be remembered, though, that a four-dimensional color space is fundamentally different from a three-dimensional one: strictly speaking, the two color spaces are incommensurable, for there is no way to map the kinds of distinctions available in four dimensions into the kinds of distinctions available in three dimensions without remainder. We can, of course, obtain some analogical insights into what such higher dimensional color spaces might be like. We could imagine, for example, that our color space contains an additional temporal dimension. In this analogy, colors would flicker to different degrees in proportion to the fourth dimension. Thus to use the term pink, for example, as a designator in such a four-dimensional color space would be insufficient to pick out a single color: one would have to say rapid-pink, etc. If it turns out that the color space of diurnal birds is pentachromatic (which is indeed possible), then we are simply at a loss to envision what their color experience could be like. It should now be apparent, then, that the vastly different histories of structural coupling for birds, fishes, insects, and primates have enacted or brought forth different perceived worlds of color. Therefore, our perceived world of color should not be considered to be the optimal “solution” to some evolutionarily posed “problem.” Our perceived world of color is, rather, a result of one possible and viable phylogenic pathway among many others realized in the evolutionary history of living beings. Again, the response on the behalf of the “received view” of evolution in cognitive science will be, “Very well, let us grant that color as an attribute of our perceived world cannot be explained simply by invoking some optimal fit, since there is such a rich diversity of perceived worlds of color. Thus the diverse neuronal mechanisms underlying color perception are not different solutions to the same evolutionarily posed problem. But all that follows is that our analysis must be made more precise. These various perceived worlds of color reflect various forms of adaptation to diverse ecological niches. Each animal group optimally exploits different regularities of the world. It is still a matter of optimal fit with the world; it is just that each animal group has its own optimal fit.” This response is a still more refined form of the evolutionary argument. Although optimizations are considered to differ according to the species in question, the view remains that perceptual and cognitive tasks involve some form of optimal adaptation to the world. This view represents a sophisticated neorealism, which has the notion of optimization as its central explanatory tool. We cannot proceed further, then, without examining more closely this idea in the context of evolutionary explanations. We cannot attempt to summarize the state of the art of evolutionary biology today, but we do need to explore some of its classical foundations and their modern alternatives.

Body-knowledge: what is it?

I use the term“body-knowledge”  in my dissertation research primarily to refer to the experience of knowing about one’s own body, and especially embracing perception and assessments of the body through the body.  It is meant to straddle the classic cognitive psychology distinction between explicit knowledge that is verbalizable, and implicit knowledge that may only be revealed through experiments. Trying to define the term brings up a number of questions:

-How is “neurophysiological information-processing” related to “body- knowledge”?

-To what extent does the distinction between conscious and unconscious knowledge need to be invoked to explain that relationship?

-Should beliefs about the body be understood as part of body knowledge? What about attitudes, expectations, and desires concerning one’s body?

-Do the properties of the body vis-à-vis external objects and the external environment factor in, such as my knowledge of my ability to lift x kilograms of weights, or to effect changes in the world with my body?

-How is body-knowledge related to body-state information access?

This latter phrase can be thought of as “internal perception of information about the body”. For present purposes a heuristic understanding probably should suffice: body-state information access refers to what content an individual can perceive, sense, or detect about their body, but also to putative notions of information-processing in the afferent or other nerves that produce the content. As the term “cognition” signifies both mind as a collection of unconscious systems and (however problematically) mind as consciously experienced, body-state information access, as I use the phrase, straddles the divide between subjective and objective aspects of the body (compare to Merleau-Ponty’s (1968) notion of the “corporeal” or “the flesh”). One might extend the concept to mean that body-state information access also refers to a sort of “information gain” in bodily perception: for instance, being aware of digestive processes where one was not previously.

Interoception is another term needing examination: while classically interoception refers to perception of the visceral organs in the inside of the body, consider Bud Craig’s (2002) proposed redefinition (pg.655):

“Interoception should be redefined as the sense of the physiological condition of the whole body (including pain and temperature), and not just of the viscera”

Even if this broader sense becomes accepted, interoception will still include the sense of “interior perception”.  The more expansive signification should then overlap with somatic cognition, a term deployed by neuroscientists (Tanosaki, Suzuki, and Kimura, 2002) who use it to signify perception using body parts such as fingers, and also internal cognition, or even visceral cognition, labels used by researchers who model the relationship of the internal organs to the nervous system and perception (Adam, 1998, pg 156-159).

Compare these to body cognition, which might not only embrace the idea of knowledge of one’s lived, experienced body, “thinking with the body,” but also the somatic, visceral,  neurophysiological, and cognitive systems making the perception and knowledge possible. “Body cognition” would seem to have experiential or phenomenological (that is, felt) dimensions, but should also refer to what are commonly understood to be unconscious mental, neural, and other physiological processes enabling this knowing. The profusion of terms may reflect the inherent complexity of the systems involved, our partial and provisional understanding, or both. Analyzing how the notion of information relates to models that explain how unconscious neurophysiological processes give rise to conscious ones is a particular focus of my project.

As I will be use the term, body-knowledge embraces the notion of using the body as the means to perceive or assess itself, such as with symptom perception. The study of body cognition involves perspectives from many fields, but could be understood as a subset of embodied cognitive science, which differs from standard approaches to the extent that it emphasizes overcoming the Cartesian split between subject and object implicit in cognitive science, and the coupling of human mental activity to a meaningful world. One of the goals of a cognitive science of embodiment would be to construct a model of body knowledge good enough to explain how the embodied brain and mind make knowledge of the body, sensing or perceiving using the body, and the ability of people to use directed attention and introspection to gain “true information” or validated knowledge (compare to beliefs) about the body.

As I use the terms, body-knowledge and body-state information access refer to both experiential-phenomenological knowledge (“I feel hungry” or “I have an itch on my scalp, but not as bad as earlier”) that may form the basis of verbal reports as well as the unconscious, and presumably not explicitly stateable, underlying information processes comprising cognition. This distinction between stable and explicit and non-stateable or implicit knowledge is not a trivial one. Cognitive science, neuroscience, and psychophysiology propose that our conscious awareness and experience of information about the body to be to be somehow made of or caused by unconscious information, because cognitive processes are understood to be mostly unconscious.  Varela, Thompson, and Rosch (1991, pg. 49) point out that cognitive science:

“…postulates processes that are mental but that cannot be brought into consciousness at all. Thus we are not simply unaware of the rules that govern the generation of mental images or of the rules that govern visual processing; we could not be aware of these rules. Indeed, it is typically noted that if such cognitive processes could be made conscious, then they could not be fast and automatic and so could not function properly”

neurophenomenology and body alienation in cognitive science

It is worth exploring the historical, Cartesian “body alienation”, or default privileging of depersonalized, dismebodied, system-centric theories of mind, of much or most of the fields grouped under the label of cognitive science and neuroscience. Psychologists, linguists, philosophers, and neuroscientists have spent decades using computational and information-processing metaphors and models to explain behavior, problem-solving, memory, syntax, and other phenomena. The need to construct a theoretical bridge from brain-biology to mind-science led to the deployment of high-level abstractions such as “symbol,” “algorithm,” “information,” and “representation.” A standard view would be that recognizing features of the world, generating language, rational problem solving, recognizing patterns, and other cognitive operations are enabled by “computations over mental representations.” This may be a useful construct, and the notion of representation need not be solely of the symbolic and rule-based sort that apeared in the 1950-s and 1960’s, but the idea that cognitive scientists, linguists, and pychologists can be “implementation agnostic” and unconcerned with the biological details underlying the mind seems very dated.

Neurobiologists and experimental psychologists took note of the interdisciplinary cybernetics movement in the post-war period, and also adopted such (arguably under-defined) notions to make sense of otherwise low-level systems and phenomena (Werner, 2005). The multi-disciplinary cognitive science research program used core ideas of computation, representation, and information-processing to model a variety of mental systems and phenomena, but the behaviorist influence remained, typically constraining research to the more-readily modeled “objective” aspects of mind.

The theoretical and methodological difficulties associated with modeling emotions, conscious awareness, perception, and body knowledge disorders provided openings for a revised cognitive science and psychology that has come to be called neurophenomenology, or enactive cognitive neuroscience, which emphasizes:

-in contrast to representationalist theories, human cognition does not so much represent features of the outside world as it enables the mind to enact, co-constitute, or co-construct an experienced, perceived environment (Varela, Thompson, and Rosch, 1991) (Merleau-Ponty, 1962) via evolutionarily-selected sensorimotor systems (Lewontin, 1983)

-unlike many traditional cognitive models which look at mental activity “objectively” or from a Cartesian outside standpoint, as a system, the notion of embodiment in cognitive science privileges the notion that mental life is grounded in the lived body, which is to say, cognition has aspects which we are personally aware of and of which we experience consciously and bodily, (or, better, that are phenomenologically lived and felt)

-a recognition that verbal reports from people may very well be a critical and necessary source of data and insight for understanding the conscious, embodied character of mental and neural activity.

-an insistence that data developed from traditional, externalistic, “system-centric” based ideas and models of “mind” or “mental activity” or “cognition” psychology, cognitive science, neuroscience, and other disciplines such as informatics, human-computer interaction need to be re-examined in the light of the above concepts.

A succinct description of how mind and brain are understood in the embodied cognition mode of thinking was offered by Varela (1999, pp. 71-89):

“We tend to think that the mind is in the brain, in the head, but the fact is that the environment also includes the rest of the organism; includes the fact that the brain is intimately connected to all of the muscles, the skeletal system, the guts, and the immune system, the hormonal balances and so on and so on. It makes the whole thing into an extremely tight unity. In other words, the organism as a meshwork of entirely co-determining elements makes it so that our minds are, literally, inseparable, not only from the external environment, but also from what Claude Bernard already called the milieu intérieur, the fact that we have not only a brain but an entire body“