Supersizing the Mind

Supersizing the Mind: Embodiment, Action, and Cognitive Extension, a recent book by philosopher Andy Clark is reviewed by Melvyn Goodale in Nature, and I pass on some clips from his review, because Clark's views exactly mirror the sentiments expressed in my Biology of Mind Book:

In Supersizing the Mind, philosopher Andy Clark makes the compelling argument that the mind extends beyond the body to include the tools, symbols and other artefacts we deploy to engage the world. According to Clark and other proponents of the 'extended mind' hypothesis, the laptop on which I am writing this review is coupled to my brain and has become part of my mind. Manipulating sentences on the screen can prompt new insights and new ways of conveying ideas, a reiterative cognitive process that would be difficult to achieve without such a tool. The same argument applies to my BlackBerry, to the white board in my office, and even to the conversations I might have with my colleagues. Cognition, Clark argues, is not 'brain-bound' but a dynamic interaction between the neural circuits inside our skulls, our bodies and the objects and events in the outside world.

Clark explores in detail the consequences of embodied and extended cognition for our conscious perception of the world. He acknowledges that the "intimacy of brain, body, world, and action" must have implications for our perceptual experience, but ultimately rejects the idea of enactive perception championed by philosopher Alva Noë, in which our experience is seen as nothing more than the sensorimotor routines that we use to interact with the world. For Clark, perception is shaped by the way in which we explore this world. But at the same time, he argues, our conscious experience of objects and events is not bound to the details of the sensorimotor routines that mediate that exploration. These routines, he suggests, are controlled by encapsulated systems with operating characteristics that are not privy to conscious, or even unconscious, scrutiny and whose activity is removed from the information they convey. In rejecting Noë's sensorimotor model, Clark argues that conscious perception does not depend on a "common sensorimotor currency" but arises from a subtle interplay between brain, body and environment, "replete with special-purpose streaming and with multiple, quasi-independent forms of internal, and external, representation and processing".

If Clark is right, and I think he is, then simply studying what goes on in the brain will tell us only part of what happens as cognitive activity unfolds. To capture the richness of thought, we have to step outside the box and embrace the world beyond the skull.

The epistemology of everything

I thought this essay was so striking that I want to pass it on in its entirety (I started to excerpt chunks, but found every sentence worthwhile, and so stopped). It is completely consonant with the ideas in my "I-Illusion" lecture and podcast.

Understanding that the outside world is really inside us and the inside world is really outside us will change everything. Both inside and outside. Why?.."There is no out there out there", physicist John Wheeler said in his attempt to explain quantum physics. All we know is how we correlate with the world. We do not really know what the world is really like, uncorrelated with us. When we seem to experience an external world that is out there, independent of us, it is something we dream up...Modern neurobiology has reached the exact same conclusion. The visual world, what we see, is an illusion, but then a very sophisticated one. There are no colours, no tones, no constancy in the "real" world, it is all something we make up. We do so for good reasons and with great survival value. Because colors, tones and constancy are expressions of how we correlate with the world...The merging of the epistemological lesson from quantum mechanics with the epistemological lesson from neurobiology attest to a very simple fact: What we percieve as being outside of us is indeed a fancy and elegant projection of what we have inside. We do make this projection as as result of interacting with something not inside, but everything we experience is inside...Is it not real? It embodies a correlation that is very real. As physicist N. David Mermin has argued, we do have correlations, but we do not know what it is that correlates, or if any correlata exists at all. It is a modern formulation of quantum pioneer Niels Bohr's view: "Physics is not about nature, it is about what we can say about nature."

So what is real, then? Inside us humans a lot of relational emotions exists. We feel affection, awe, warmth, glow, mania, belonging and refusal towards other humans and to the world as a whole. We relate and it provokes deep inner emotional states. These are real and true, inside our bodies and percieved not as "real states" of the outside world, but more like a kind of weather phenomena inside us...That raises the simple question: Where do these internal states come from? Are they an effect of us? Did we make them or did they make us? Love exists before us (most of us were conceived in an act of love). Friendship, family bonds, hate, anger, trust, distrust, all of these entities exist before the individual. They are primary. The illusion of the ego denies the fact that they are there before the ego consciously decided to love or hate or care or not. But the inner states predate the conscious ego. And they predate the bodily individual...The emotional states inside us are very, very real and the product of biological evolution. They are helpful to us in our attempt to survive. Experimental economics and behavioral sciences have recently shown us how important they are to us as social creatures: To cooperate you have to trust the other party, even though a rational analysis will tell you that both the likelihood and the cost of being cheated is very high. When you trust, you experience a physiologically detectable inner glow of pleasure. So the inner emotional state says yes. However, if you rationally consider the objects in the outside world, the other parties, and consider their trade-offs and motives, you ought to choose not to cooperate. Analyzing the outside world makes you say no. Human cooperation is dependent on our giving weight to what we experience as the inner world compared to what we experience as the outer world.

Traditionally, the culture of science has denied the relevance of the inner states. Now, they become increasingly important to understanding humans. And highly relevant when we want to build artefacts that mimic us...Soon we will be building not only Artificial Intelligence. We will be building Artificial Will. Systems with an ability to convert internal decisions and values into external change. They will be able to decide that they want to change the world. A plan inside becomes an action on the outside. So they will have to know what is inside and outside...In building these machines we ourselves will learn something that will change everything: The trick of perception is the trick of mistaking an inner world for the outside world. The emotions inside are the evolutionary reality. The things we see and hear outside are just elegant ways of imagining correlata that can explain our emotions, our correlations. We don't hear the croak, we hear the frog.

When we understand that the inner emotional states are more real than what we experience as the outside world, cooperation becomes easier. The epoch of insane mania for rational control will be over...What really changes is they way we see things, the way we experience everything. For anything to change out there you have to change everything in here. That is the epistemological situation. All spiritual traditions have been talking about it. But now it grows from the epistemology of quantum physics, neurobiology and the building of robots...We will be sitting there, building those Artificial Will-robots. Suddenly we will start laughing. There is no out there out there. It is in here. There is no in here in here. It is out there. The outside is in here. Who is there?

That laughter will change everything.

Soul-travel for selfless beings

Thomas Metzinger, one of my favorite philosophers, offers this piece on this years Edge.org question "What will change everything."

John Brockman points out that new technology leads not only to new ways of perceiving ourselves, but also to a process he calls "recreating ourselves." Could this become true in an even deeper and more radical way than through gene-technology? The answer is yes.

It is entirely plausible that we may one day directly control virtual models of our own bodies directly with our brain. In 2007, I first experienced taking control of a computer-generated whole-body model myself. It took place in a virtual reality lab where my own physical motions were filmed by 18 cameras picking up signals from sensors attached to my body. Over the past two years, different research groups in Switzerland, England, Germany and Sweden have demonstrated how, in a passive condition, subjects can consciously identify with the content of a computer-generated virtual body representation, fully re-locating the phenomenal sense of self into an artificial, visual model of their body.

In 2008, in another experiment, we saw that a monkey on a treadmill could control the real-time walking patterns a humanoid robot via a brain-machine interface directly implanted into its brain. The synchronized robot was in Japan, while the poor monkey was located thousands of miles away, in the US. Even after it stopped walking, the monkey was able to sustain locomotion of the synchronized robot for a few minutes—just by using the visual feedback transmitted from Japan plus his own "thoughts" (whatever that may turn out to be).

Now imagine two further steps.

First, we manage to selectively block the high-bandwidth "interoceptive" input into the human self-model—all the gut feelings and the incessant flow of inner body perceptions that anchor the conscious self in the physical body. After all, we already have selective motor control for an artificial body-model and robust phenomenal self-identification via touch and sight. By blocking the internal self-perception of the body, we could be able to suspend the persistent causal link to the physical body.

Second, we develop richer and more complex avatars, virtual agents emulating not only the proprioceptive feedback generated by situated movement, but also certain abstract aspects of ongoing global control itself—new tools, as Brockman would call them. Then suddenly it happens that the functional core process initiating the complex control loop connecting physical and virtual body jumps from the biological brain into the avatar.

I don't believe this will happen tomorrow. I also don't believe that it would change everything. But it would change a lot.

Some clarity on alternative therapies and medical science

Mindblog reader Ian has pointed me to this essay on alternative medicine and new age spirituality by Bruce Charlton, at the University of Newcastle upon Tyne. His website contains other interesting bits of writing. He paints what I think should be a useful and clear distinction:

I would define alternative therapies in terms of them having non-scientific explanations. In so far as a therapy does have a biological explanation, I would regard that therapy as simply part of orthodox medicine. The crucial difference between orthodox and alternative therapies is therefore that alternative medical systems have non-scientific explanations based on spiritual, mystical, legendary or otherwise intuitively-appealing insights...I am broadly supportive of alternative and complementary therapies because I think that overall they do a great deal of good for a large number of people. But the kind of good they do is psychological and spiritual; not medical. They are about making people feel better (‘healing’) not mending their dysfunctional brains and bodies (‘curing’). Alternative therapies certainly are not a part of medical science. So, on the one hand, I would like to see alternative therapies thrive and spread, and on the other hand they should drop all their pretensions to ‘scientific’ validity. In future, alternative medicine should explicitly become part of New Age spirituality, and thereby clearly be differentiated from orthodox medicine and biological science.

He argues against the relevance of randomized trials to test alternative therapies:

...when randomised trials are used in alternative medicine, the usual process of therapeutic development is turned on-its-head. Instead of coming at the end of a long process of scientific evaluation, randomized trials are placed at the beginning of evaluation, and are indeed expected to be the only form of scientific evaluation – with randomization used in isolation with no possibility for cross-checking using other scientific methods...The problem is not so much that alternative therapy systems are scientifically primitive; it is that alternative systems are not scientific at all. By definition they do not have scientifically-grounded explanations. When the constraints of randomized trials are properly understood, it becomes clear that 'positive' trials in alternative medicine are irrelevant.

His summary:

Orthodox medicine is based on scientific theories and is properly characterized by objective evaluation criteria and formal professional structures of education and certification. Alternative healing deploys a wide range of intuitively-appealing but non-scientific explanations, and constitutes a consumer-dominated marketplace of ideas and therapies which are personally-evaluated by the client...Orthodox medicine focuses on curing disease and promoting health. But alternative therapies should be based on promoting well-being and personal fulfillment. To do this they need to be able freely to deploy poetic explanations and charismatic healers as part of the wide and growing practice of New Age spirituality.

How do you feel — now? The anterior insula and human awareness

In a perspectives article in Nature Neuroscience Bud Craig proposes that the anterior insula plays a fundamental role in human awareness (if you simply enter 'anterior insula' in google images you can see depictions of the structures for yourself, or see the figure below). Here is his abstract, followed by a description of the structure and then his model for the involvement of the insula in awareness:

The anterior insular cortex (AIC) is implicated in a wide range of conditions and behaviours, from bowel distension and orgasm, to cigarette craving and maternal love, to decision making and sudden insight. Its function in the re-representation of interoception offers one possible basis for its involvement in all subjective feelings. New findings suggest a fundamental role for the AIC (and the von Economo neurons it contains) in awareness, and thus it needs to be considered as a potential neural correlate of consciousness.

A photograph of the left insular cortex of a human patient. The human insular cortex is a distinct but hidden lobe of the brain. It is disproportionately (approx30%) enlarged in the human relative to the macaque monkey. It has 5–7 oblique gyri, but its morphology is quite variable, even between the two sides. Primary interoceptive representations are located in the dorsal posterior insula and re-represented in a polymodal integrative zone in the mid-insula and again in the anterior insular cortex (AIC). The primary interoceptive, gustatory and vagal representations extend to the anterior limit of the insula in macaques but only to the middle of the insula in humans, which suggests that the AIC of humans has no equivalent in the monkey. The most anterior and ventral (inferior) portion of the human insula that adjoins the frontal operculum is probably the most recently evolved, because this part (as well as the anterior cingulate cortex) contains von Economo neurons. as, anterior short insular gyrus; al, anterior long insular gyrus; ac, accessory gyrus; APS, anterior peri-insular sulcus; H, Heschl's gyrus; IPS, inferior peri-insular sulcus; ms, middle short insular gyrus; ps, posterior short insular gyrus; pl, posterior long insular gyrus; SPS, superior peri-insular sulcus. Photograph is courtesy of Professor Thomas P. Naidich, Mount Sinai Medical Center, New York.

Cartoons illustrating features of the proposed structural model of awareness. a | The posited integration of salient activity, progressing from the posterior insula (left) to the anterior insula (right). The primary interoceptive representations of feelings from the body provide a somatotopic foundation that is anchored by the associated homeostatic effects on cardiorespiratory function, as indicated by the focus of the colours in the chest. The integration successively includes homeostatic, environmental, hedonic, motivational, social and cognitive activity to produce a 'global emotional moment', which represents the sentient self at one moment of time. b | The top cartoon shows how a series of global emotional moments can produce a cinemascopic 'image' of the sentient self across time. The lower cartoon shows how the proposed model can produce a subjective dilation of time during a period of high emotional salience, when global emotional moments are rapidly 'filled up'. ACC, anterior cingulate cortex; DLPFC, dorsolateral prefrontal cortex; VMPFC, ventromedial prefrontal cortex.

Embodied cognition, a cold stare makes you feel cold.

I show below the abstract from Zhong and Leonardelli, followed by more explanation from an article by Benedict Carey.

Metaphors such as icy stare depict social exclusion using cold-related concepts; they are not to be taken literally and certainly do not imply reduced temperature. Two experiments, however, revealed that social exclusion literally feels cold. Experiment 1 found that participants who recalled a social exclusion experience gave lower estimates of room temperature than did participants who recalled an inclusion experience. In Experiment 2, social exclusion was directly induced through an on-line virtual interaction, and participants who were excluded reported greater desire for warm food and drink than did participants who were included. These findings are consistent with the embodied view of cognition and support the notion that social perception involves physical and perceptual content. The psychological experience of coldness not only aids understanding of social interaction, but also is an integral part of the experience of social exclusion.

More detail on the two experiments:

In one, they split 65 students into two groups, instructing those in one to recall a time when they felt socially rejected, and those in the other to summon a memory of social acceptance.

Many of the students were recent immigrants and had fresh memories of being isolated in the dorms, left behind while roommates went out, Dr. Zhong said.

The researchers then had each of the participants estimate the temperature in the lab room. The students who had recalled being excluded estimated the temperature to be, on average, 5 degrees Fahrenheit lower than the others.

In the second experiment, the researchers had 52 students come into the lab and play a computer game, one at a time. The students “threw” a ball back and forth with three other figures on the computer screen that — so the participants thought — represented other students playing from remote locations.

In fact a computer program was running the game, and it excluded half the study participants, throwing them the virtual ball a couple of times in the beginning, then ignoring them altogether. The other group of students in the study were included in the virtual game of catch.

After playing the game, the participants in this study then rated their preferences for a variety of foods and drinks, including hot soup, coffee, an apple and crackers. Those who had been isolated in the computer game showed a strong preference for the soup and coffee over the other items; the included students had no such preference.

Our somatosensory cortex embodies the facial expressions of others

The Editor's choice section of science describes an interesting bit of work by Pitcher et al. showing the embodyment of our social cognition:

Humans are especially interested in faces, as a means of sending signals--witness the sizeable arc of somatosensory cortex devoted to representation of one's own face--and as a substrate for social cognition. Pitcher et al. describe results supporting theories of embodied cognition and emotion, which posit cognition and emotion as being shaped by our bodily movements and perceptions. They used repetitive transcranial magnetic stimulation (rTMS) to interfere with neural activity in the face areas of the somatosensory cortex while people discriminated the emotional expressions of faces (happy, sad, surprised, fearful, angry, and disgusted) and found that accuracy dropped significantly, as it also did when the occipital face area was similarly stimulated. The temporal sequence of neural processing was then delineated using double-pulse TMS, showing that the occipital area acted in the time window from 60 to 100 ms after the face stimulus was shown, whereas the somatosensory area was active a bit later, between 100 and 170 ms.

Embodyment and Art

I just received an email from Andrew Werth regarding the previous post. Andrew is a former software engineer turned artist whose paintings are about perception and embodiment. I thought I would pass on this link to his website, which lets one view paintings in his Embodyment Series.

Arguing for Embodied Consciousness

I thought I would pass along portions of a review in Science by Harold Fromm which has the title of this post, of Edward Slingerland's new book, "What Science Offers the Humanities - Integrating Body and Culture."

...his overall task is to address the befuddled dualism that still dominates most of our intellectual disciplines...Slingerland's central theme is that everything human has evolved in the interests of the materiality of the body. He identifies objectivist realism and postmodern relativity, both insufficiently attentive to the body, as the major epistemologies to be swept away, followed by the dualism of body and soul. For Slingerland, the presiding genii behind such a cleansing are George Lakoff and Mark Johnson, with heavier debts to Johnson [whose terse summary of embodiment in (1) appeared too late for Slingerland to reference]. They view all thought and human behavior as generated by the body and expressed as conceptual metaphors that translate physical categories (such as forward, backward, up, and down) into abstract categories (such as progress, benightedness, divinity, immorality). These body-driven metaphors, Slingerland writes, are a "set of limitations on human cognition, constraining human conceptions of entities, categories, causation, physics, psychology, biology, and other humanly relevant domains."

The supposedly objective world is not "some preexisting object out there in the world, with a set of invariant and observer-independent properties, simply waiting to be found the way one finds a lost sock under the bed." All we can ever see or understand is what our own bodily faculties permit via the current structure of the brain.

In opposition to objective realism, postmodern relativity regards language and culture as constituting the only "real" world possible for us. It posits an endless hall of mirrors with no access to outside--epitomized by Derrida's notorious remark that there is nothing (at least for humans) outside of texts (i.e., culture). This view, which dominated the humanities for several decades, is mercifully beginning to fade as the cognitive sciences have matured and are increasingly promulgated.

Even though the knowing human subject is itself just a thing and not an immaterial locus of reason, the universe it experiences is as real and functional for us as any "thing" could possibly be. We do get some things "right," even if we can never know the noumenal genesis behind our knowledge. And the very concept of noumena (things in themselves independent of any observer) now seems somewhat obsolete, given that the intuition of discrete, self-bounded "things" is as built-in to the human psyche as the Kantian intuitions of space and time, grounding all experience.

Our million billion synapses produce a "person" with the illusion of a self. Slingerland holds that "we are robots designed to be constitutionally incapable of experiencing ourselves and other conspecifics as robots." Our innate and overactive theory of mind (that other people, like ourselves, have "intentions") projects agency onto everything--in the past, even onto stones and trees. The "hard problem" for philosophy of consciousness (to use David Chalmers's phrase) remains: what are thoughts, cogitations, thinkers, qualia? Chalmers's solution, alas, swept away Cartesian dualism only to sneak his own magic spook, conscious experience (for him, on par with mass, charge, and space-time), in through the back door (2, 3).

Slingerland starts with Darwin and eventually follows Daniel Dennett so far as to agree that consciousness can be done full justice through third-person descriptions that require no mysterious, unaccounted-for, nonmaterial, first-person entity as substrate. Thus the famous "Mary," who intellectually knows everything there is to know about color despite having been sequestered for life in a color-free lab, will recognize red the first time she steps outside (4). And Thomas Nagel's famous bats don't know anything about bathood that we can't figure out for ourselves from observation (5). No first-person construct, no locus of consciousness, need be invoked.

The next step, if you want to go so far (the jury is out), is to eliminate consciousness altogether, because there's nothing for it to do that can't be done without it. And with it, you need a spook to keep the show on the road. Choose your insoluble problem: eliminate consciousness altogether as superfluous or explain it (if there's really a you who makes such choices). Slingerland prefers the first option.

His conclusion, which I can hardly do justice to here, is relatively satisfying. He notes that although we don't have great difficulty knowing that Earth revolves around the Sun while feeling that the Sun is rising and setting (Dennett's favorite example of folk psychology), "no cognitively undamaged human being can help acting like and at some level really feeling that he or she is free"--however nonsensical the notion of agencyless free will (i.e., "choices" without a self to make them). Still, once the corrosive acid of Darwinism [to use Dennett's figure from (6)] has resolved the body-mind dualism into body alone, some but not most of us are able "to view human beings simultaneously under two descriptions: as physical systems and as persons."

References

1. M. Johnson, The Meaning of the Body: Aesthetics of Human Understanding (Univ. of Chicago Press, Chicago, 2007).
2. D. J. Chalmers, J. Consciousness Stud. 2, 200 (1995).
3. D. J. Chalmers, The Conscious Mind: In Search of a Fundamental Theory (Oxford Univ. Press, Oxford, 1996).
4. F. Jackson, Philos. Q. 32, 127 (1982).
5. T. Nagel, Philos. Rev. 83, 435 (1974).
6. D. C. Dennett, Darwin's Dangerous Idea: Evolution and the Meaning of Life (Simon and Schuster, New York, 1995).

Phantom Penises In Transsexuals

In an article in the Journal of Consciousness Studies, Ramachandran and McGeoch offer evidence of an innate gender-specific body image in the brain:

How the brain constructs one’s inner sense of gender identity is poorly understood. On the other hand, the phenomenon of phantom sensations — the feeling of still having a body-part after amputation — has been much studied. Around 60% of men experience a phantom penis post-penectomy. As transsexuals report a mismatch between their inner gender identity and that of their body, we wondered what could be learned from this regarding innate gender-specific body image. We surveyed male-to-female transsexuals regarding the incidence of phantoms post-gender reassignment surgery. Additionally, we asked female-to-male transsexuals if they had ever had the sensation of having a penis when there was not one physically there. In post-operative male-to-female transsexuals the incidence of phantom penises was significantly reduced at 30%. Remarkably, over 60% of female-to-male transsexuals also reported phantom penises. We explain the absence/presence of phantoms here by postulating a mismatch between the brain’s hardwired gender-specific body image and the external somatic gender. Further studies along these lines may provide penetrating insights into the question of how nature and nurture interact to produce our brain-based body image.

Simon LeVay, an expert on human sexuality, does make the point that Ramachandran is comparing those who are extremely pleased with getting rid of their penis to others who are distressed and think about their penis all the time. It would appear that Ramachandran has largely left out emotions, and also the question of wishful thinking.

Love speed dating

You may do better in relying on your impression after only 4 minutes of interaction with a potential partner than if you think about it a lot. Here is an engaging essay by Matt Kaplan.

The Blakeslees on the body's own mind...

"The Body Has a Mind of Its Own" is the title of a book being released today, September 11, by Sandra Blakeslee (N.Y.Times Science writer) and her son Matthew Blakeslee (also a science writer, making him the fourth generation of science writers in the family line!). Its subject is the maps that our brain makes of our internal and external worlds, including our feelings, emotions, and sense of self... and how plastic they can be. Much of the work they describe has been the subject of posts on this MindBlog. I enjoyed reading the book, and would highly recommend it. It crams an amazing amount of material into a small space. It is easy to read and engaging.

Here is one of the figures from the book, illustrating how our brain cells adapt to tool use, incorporating the tool into our body image.

How our brain changes when we (or monkeys, as in the figure) use a hand tool to extend our reach. Legend. a) Before learning to use a rake (left) or while passively holding the rake (right) without the intention of using it as a tool, the monkey's hand-centered visual-tacile receptive fields stay confined to the hand's immediate vicinity. But while the monkey is actively wielding the rake (center), the cells' visual receptive fields expand along its length. (Visual or tactile input to the shaded area causes a hand-centered cell in the parietal lobe to fire.) b). The visual-tacile receptive field expansion of one of the monkey's shoulder-centered neurons.

These positive points having been made, I felt during my reading like I was looking over the authors' shoulders as they were writing, and I kept wanting to suggest that the presentation be tightened up with more bottom lines brought up front. Many times I had the "Ah Ha!, why didn't they tell me THIS is where they were going" experience. With one study after another thrown onto the page I found myself loosing the thread. When I did find an interesting nugget I had not be aware of, I was frustrated by the fact that there is no bibliography or list of references provided. It would be very useful for the authors to provide such references on a website associated with the book.

There are many excellent summaries and quotable passages in the book. I like the ending paragraphs, which follow a discussion of the neural correlates of our sense of self, and how distortions in our sense of ownership can occur. A few clips:

So, is the self ultimately "just" an illusion?...According to the neuroscience of body maps - and incidentally, the majority of Eastern religions - in many respects, yes...A key point is that your mind feels like a seamless whole when "all your faculties" are working. But if your body mandala were to go on the fritz in one of a hundred ways, whether through damage to one map or several, or through a severing of between-map connections, you might suddenly experience extra arms, a phantom leg...hemineglect (where half the universe winks out of your awareness), alien hand syndrome, and all manner of delusions and misperceptions. Case studies of brain damage like these are one of the biggest philosophical, not to mention logical, arguments against the idea of a uniatry psychic core. When certain parts of the brain break, certain parts of the mind break; the illusion is spoiled, and the underlying multifariousness of the psyche is exposed......The illusion of the self is that self is a kernel, rather than a distributed, emergent system....Localizations of psychic functions are better said to exist in loops of information processing, or circuits, rather than specific points...the...psychic self...is an orchestra without a conductor or a fixed score, but whose players are so good at collaborative improv that wonderful music keeps flowing out of it. Just as the orchestra has no score and no conductor, the mind has no kernel, no "little man" sitting at the center of the fray directing the action. But it is teeming with noncentral "little men," the brain's motley team of homunculi, who form the backbone of the whole production. And you, thankfully, have the irreducible illusion of being the conductor of yours life's music in all its complexity, emotional nuace, crescendo and diminuendo - the ballad that is the you-ness of you."

How the body shapes intelligence

Kitano reviews a new book in Nature (PDE of review here): How the Body Shapes the Way We Think: A New View of Intelligence. by Rolf Pfeifer & Josh Bongard, Bradford Books: 2006. A few clips:

...a chess computer, unlike a human, does not have a body to enable it to interact with its environment, for example. This distinction differentiates two views on intelligence. One view is that intelligence is independent of the body and is unaffected by its existence, shape and function. The other view is that intelligence is contained within a physical body and that the body shapes the mind, an idea often referred to as physical embodiment or the presence of a behaviour-based agent.

The Pfeifer and Bongard book offers perspective on how artificial-intelligence and robotics researchers are dealing with the increasing recognition in the artificial-intelligence and robotics communities that the nature of the body significantly affects the mind, although it does not totally control it. The book focuses on artificial agents, but with a lot of inspiration from nature.

One salient difference between the intelligent agents discussed in this book and traditional artificial-intelligence systems, as represented by chess computers, is the contextual thickness of system behaviours. Many of the robotics systems discussed in the book can cope, at least to some extent, with changes in the expected environment, tasks and other assumed conditions, whereas chess computers and other traditional artificial-intelligence systems are usually extremely fragile when faced with even a small change in such conditions. Behaviour-based robots should be able to perform almost flawlessly if the size of road or unevenness of terrain deviates from the initial assumption. However, the results will be catastrophic if a chess computer is given a chess board with nine rows and columns, rather than eight, as they are tuned specifically for the existing rules of chess. Imagine a thought experiment on a chess game between a behaviour-based system and an existing chess computer. The chess computer would be unbeatable with the defined rules, but if the rules were modified the behaviour-based system may do better.

Threatening the rubber hand illusion..cortical anxiety

Ehrsson et al. report an interesting extension of work on illusory feelings of body ownership:

The feeling of body ownership is a fundamental aspect of self-consciousness. The underlying neural mechanisms can be studied by using the illusion where a person is made to feel that a rubber hand is his or her own hand by brushing the person's hidden real hand and synchronously brushing the artificial hand that is in full view. Here we show that threat to the rubber hand can induce a similar level of activity in the brain areas associated with anxiety and interoceptive awareness (insula and anterior cingulate cortex) as when the person's real hand is threatened. We further show that the stronger the feeling of ownership of the artificial hand, the stronger the threat-evoked neuronal responses in the areas reflecting anxiety. Furthermore, across subjects, activity in multisensory areas reflecting ownership predicted the activity in the interoceptive system when the hand was under threat. Finally, we show that there is activity in medial wall motor areas, reflecting an urge to withdraw the artificial hand when it is under threat. These findings suggest that artificial limbs can evoke the same feelings as real limbs and provide objective neurophysiological evidence that the rubber hand is fully incorporated into the body. These findings are of fundamental importance because they suggest that the feeling of body ownership is associated with changes in the interoceptive systems.

Figure legend - Linear relationship between ownership and the anxiety responses in the bilateral anterior insula and bilateral ACC (circled). A regression analysis identified a significant relationship between the vividness ratings of the rubber-hand illusion obtained during the scans and the parameter estimates for the contrast between threat during ownership and threat during no ownership in left insula

Embodying emotion

This is the title of an interesting review by Niedenthal (PDF here) on how manipulations of facial expression and posture in the laboratory can influence how emotions are processed. Whether we are similing or frowning, or hunched over or upright, can profoundly influence our emotional reactions to positive or negative input. Here is the abstract:

Recent theories of embodied cognition suggest new ways to look at how we process emotional information. The theories suggest that perceiving and thinking about emotion involve perceptual, somatovisceral, and motoric reexperiencing (collectively referred to as "embodiment") of the relevant emotion in one's self. The embodiment of emotion, when induced in human participants by manipulations of facial expression and posture in the laboratory, causally affects how emotional information is processed. Congruence between the recipient's bodily expression of emotion and the sender's emotional tone of language, for instance, facilitates comprehension of the communication, whereas incongruence can impair comprehension. Taken all together, recent findings provide a scientific account of the familiar contention that "when you're smiling, the whole world smiles with you."

Two ways in which facial expression has been manipulated in behavioral experiments. (Top) In order to manipulate contraction of the brow muscle in a simulation of negative affect, researchers have affixed golf tees to the inside of participants' eyebrows. Participants in whom negative emotion was induced were instructed to bring the ends of the golf tees together, as in the right panel. [Photo credit: Psychology Press]. (Bottom) In other research, participants either held a pen between the lips to inhibit smiling, as in the left panel, or else held the pen between the teeth to facilitate smiling.

A neural link between hand muscle excitability and numerical counting

Sato et al. do an interesting experiment showing that excitability of our hand muscles changes when we perform a visual (non-numerical) counting task, reinforcing the idea that finger counting represents an basic embodied strategy for number learning. (PDF here.) Their abstract:

Developmental and cross-cultural studies show that finger counting represents one of the basic number learning strategies. However, despite the ubiquity of such an embodied strategy, the issue of whether there is a neural link between numbers and fingers in adult, literate individuals remains debated. Here, we used transcranial magnetic stimulation to study changes of excitability of hand muscles of individuals performing a visual parity judgment task, a task not requiring counting, on Arabic numerals from 1 to 9. Although no modulation was observed for the left hand muscles, an increase in amplitude of motor-evoked potentials was found for the right hand muscles. This increase was specific for smaller numbers (1 to 4) as compared to larger numbers (6 to 9). These findings indicate a close relationship between hand/finger and numerical representations.

Motor cortex for the hand and numerical counting

The April 2007 issue of the Journal of Cognitive Neuroscience has interesting articles on this topic by Andres et al. and Sato et al. Their abstracts:

Andres et al.

The finding that number processing activates a cortical network partly overlapping that recruited for hand movements has renewed interest in the relationship between number and finger representations. Further evidence about a possible link between fingers and numbers comes from developmental studies showing that finger movements play a crucial role in learning counting. However, increased activity in hand motor circuits during counting may unveil unspecific processes, such as shifting attention, reciting number names, or matching items with a number name. To address this issue, we used transcranial magnetic stimulation to measure changes in corticospinal (CS) excitability during a counting task performed silently and using either numbers or letters of the alphabet to enumerate items. We found an increased CS excitability of hand muscles during the counting task, irrespective of the use of numbers or letters, whereas it was unchanged in arm and foot muscles. Control tasks allowed us to rule out a possible influence of attention allocation or covert speech on CS excitability increase of hand muscles during counting. The present results support a specific involvement of hand motor circuits in counting because no CS changes were found in arm and foot muscles during the same task. However, the contribution of hand motor areas is not exclusively related to number processing because an increase in CS excitability was also found when letters were used to enumerate items. This finding suggests that hand motor circuits are involved whenever items have to be put in correspondence with the elements of any ordered series.

Sato et al.

Developmental and cross-cultural studies show that finger counting represents one of the basic number learning strategies. However, despite the ubiquity of such an embodied strategy, the issue of whether there is a neural link between numbers and fingers in adult, literate individuals remains debated. Here, we used transcranial magnetic stimulation to study changes of excitability of hand muscles of individuals performing a visual parity judgment task, a task not requiring counting, on Arabic numerals from 1 to 9. Although no modulation was observed for the left hand muscles, an increase in amplitude of motor-evoked potentials was found for the right hand muscles. This increase was specific for smaller numbers (1 to 4) as compared to larger numbers (6 to 9). These findings indicate a close relationship between hand/finger and numerical representations.

The End Of The 'Natural'

This stimulating essay by Andy Clark I pass on in its entirety:

I am optimistic that the human race will continue to find ways of enhancing its own modes of thought, reason, and feeling. As flexible adaptive agents we are wide open to a surprising variety of transformative bodily and mental tricks and ploys, ranging from the use of software, sports regimes and meditational practice, to drug therapies, gene therapies, and direct brain-machine interfaces.

I am optimistic that, stimulated by this explosion of transformative opportunities, we will soon come to regard our selves as constantly negotiable collection of resources, easily able to straddle and criss-cross the boundaries between biology and artifact. In this hybrid vision of our own humanity I see increased potentials not just for repair but for empowerment, expansion, recreation, and growth. For some, this very same hybrid vision may raise specters of coercion, monstering and subjugation. For clearly, not all change is for the better, and hybridization (however naturally it may come to us) is neutral rather than an intrinsic good. But there is cause for (cautious) optimism.

First, there is nothing new about human enhancement. Ever since the dawn of language and self-conscious thought, the human species has been engaged in a unique 'natural experiment' in progressive niche construction. We engineer our own learning environments so as to create artificial developmental cocoons that impact our acquired capacities of thought and reason. Those enhanced minds then design new cognitive niches that train new generations of minds, and so on, in an empowering spiral of co-evolving complexity. The result is that, as Herbert Simon is reputed to have said, 'most human intelligence is artificial intelligence anyway'. New and emerging technologies of human cognitive enhancement are just one more step along this ancient path.

Second, the biological brain is itself populated by a vast number of hidden 'zombie processes' that underpin the skills and capacities upon which successful behavior depends. There are, for example, a plethora of such unconscious processes involved in activities from grasping an object all the way to the flashes of insight that characterize much daily skilful problem-solving. Technology and drug based enhancements add, to that standard mix, still more processes whose basic operating principles are not available for conscious inspection and control. The patient using a brain-computer interface to control a wheelchair will not typically know just how it all works, or be able to reconfigure the interface or software at will. But in this respect too, the new equipment is simply on a par with much of the old.

Finally, empirical science is at last beginning systematically to address the sources and wellsprings of human happiness and human flourishing, and the findings of these studies must themselves be taken as important data points for the design and marketing of (putative) technologies of enhancement.

In sum, I am optimistic that we will soon see the end of those over-used, and mostly ad hoc, appeals to the 'natural'...

Language, embodiment, and the cognitive niche

This is the title of an essay by Andy Clark in Trends in Cognitive Sciences (Vol 10, no. 8., pp. 370-374, 2006). It discusses an alternatives to the "Pure Translation" view, stemming from Fodor, that knowing a natural language is knowing how to pair its expressions with encoding in some other, more fundamental inner code ('mentalese', or the Language of Thought). Rather language is viewed as a kind of self-constructed cognitive niche, a scaffold of words that is used to loop back upon itself to build the "thinking about thinking" that may be our best candidate for a distinctively human capacity, dependent upon language for its very existence. According to this model words and structured linguistic encoding act to stabilize and discipline (or 'anchor') intrinsically fluid and context-sensitive modes of thought and reason. Words and linguistic strings are among the most powerful and basic tools that we use to discipline and stabilize dynamic processes of reason and recall. Words, rather than being cues for the retrieval of meanings from some kind of passive storage, might be thought of as sensorily encountered items that 'act directly on mental states'. As embodied agents we are able to create and maintain a wide variety of cognitively empowering, self-stimulating loops whose activity is as much as aspect of our thinking as its result.

Looking beyond the Pure Translation view, language is treated as an aspect of thought, rather than just its public reflection. We eliminate the Central Executive where all the 'real thinking' happens and replace Pure Translation with an appeal to complex, distributed coordination dynamics: a 'wordful mind' that is populated by loops without leaders, that defies any simple logic of inner versus out, or of tool versus user... a mind where words really work.

The Neural Basis of Embodyment

Some edited clips from a recent J. Neuroscience article by Arzy et al. :

Embodiment, the sense of being localized within one's physical body, is a fundamental aspect of the self. Recent evidence has started to show that self and body processing require two distinct brain mechanisms, with key loci in the temporoparietal junction (TPJ) - involved in self processing and multisensory integration of body-related information - and the extrastriate body area (EBA) - which responds selectively to human bodies and body parts. Arzy et al have used evoked potential mapping to show that activations in EBA and TPJ code differentially for embodiment and self location, because the location and timing of brain activation depended on whether mental imagery is performed with mentally embodied (EBA) or disembodied (TPJ) self location. In a second experiment, they showed that only EBA activation, related to embodied self location, but not TPJ activation, related to disembodied self location, was modified by the subjects' body position during task performance (supine or sitting). This suggests that embodied self location and actual body location share neural mechanisms.


Figure. To investigate embodiment and self location, subjects were asked to perform two mental-imagery tasks with respect to their own body in response to a schematic front- or back-facing human figure. In an own-body transformation task, (OBT task) subjects were asked to imagine themselves in the position and orientation of a schematic human figure, as shown on a computer screen (bottom row, the correct responses for each task are indicated under each stimulus) Either the right or left hand of the figure was marked, and subjects indicated which hand was marked. In a mirror task (MIR task), the same schematic human figure was shown, but subjects were instructed to imagine that the schematic figure (as shown on the computer screen) was their mirror reflection, as seen from their habitual point of view ( top row, the correct responses for each task are indicated under each stimulus).


Figure. Generators of mirror task (MIR. top row, were localized at the left EBA and of the own body transformation task (OBT, bottom row) at the right TPJ and left EBA


Figure. EBA. The mean (x, y) Talairach coordinates of the EBA are given for several neuroimaging studies. Note the similarity of EBA localization across studies, neuroimaging techniques, and behavioral tasks.