Hughlings Himwich

Illusionism: Keith Frankish

 

 

"The only meaning is existence itself": a Conversation

Hugh: Have you read the Stephen LaBerge conversation in Blackmore’s Conversations on Consciousness?

Susan: I have. He seems to be saying that lucid living appears to entail understanding the illusion of the self and its separateness.  I like his idea that blending the Eastern spiritual and Western scientific perspectives will bring about a new understanding of consciousness.  I haven't ever had lucid dreaming so I don't know how that would affect me, but I do know that dreams are an important part of experience and our consciousness has some control over our remembrance of dreams.

Hugh: What struck me about LaBerge is his idea that consciousness is a kind of dreaming from which we can wake up, e.g. Buddha. He suggests that we might achieve a lucid consciousness where we recognize that our attachment to things, including the self, is but a story. If this insight were achieved, how would it change our lives?  Susan Blackmore has much to say about this question. My problem with consciousness being a story the brain tells itself is that my immediate perception of my experience as I type these letters and words, think these thoughts, feel the coolness of the keys, the collar too tight about my neck, the sharp ache in my heart for a loved one, this immediate sense of my own life shouts out "No, it ain't so." How do you reconcile what appear to be our abstract considerations about consciousness and your immediate perception of your own life?

Susan: I think there is merit in learning how to give up our attachment to things.  If nothing else, it may help one to be relieved of miseries and heart aches, but there is something cold and not human about the attitude that this is all a "story."  Perhaps I haven't looked deeply enough at Buddhist teachings to be saying this, but my take is that "being mindful" and aware of those miseries and heart aches is what helps us heal and that we must go through some necessary losses that are real in our lives.  It ain't so.  So, I agree with your "No, it ain't so" response to all of this.  When I started reading Susan Blackmore's comments in response to the question "Who is asking the question?" and she reached some point in her meditation where she rejected her own body as part of her self because she couldn't see her own face, I reached my limit.  I thought she was ridiculous and I was gratified to see that her own Zen teacher corrected her when he asked if she was in the room and she said "no".  He said "yes, you are here." Of course she was in the room and of course she is asking the question.  How else would she be getting royalties from her book about asking those questions?

Hugh: I do keep thinking, however, that if one could "wake up" from our normal waking experience, there would be an expansion in one's experience of existence, not as "my existence" but of existence itself.  Something like the experience of love.  LaBerge points to the illusion of consciousness as a false experience of isolation -- the true experience is identity with others and with the universe -- for LaBerge, consciousness itself is not an illusion.  That speaks very much to my own intuitions and it's probably time I own up to my own mystical inclinations.  How about your mystical inclinations? 

Susan: I have my own mystical inclinations as well, and am hoping that with my retirement, I will have time to meditate and test out this hypothesis.  Can we point to experiences that give us "identity with others and with the universe" without that waking up event?  Have you had a sense of "hyper reality" that he implies?

Hugh: Not really. Just intuitions, though I wonder about that "just."  Do you believe you have free will?

Susan: Yes.  Insofar as we make choices (of mates, of schools, of jobs we take, of presidents we vote for, etc.) I believe in free will and I believe that my brain, even if it is "just" neurons firing, helps me exercise that free will with my "executive function" in my frontal lobes.  The problem with addiction, as I gather from listening to the presentation today, is a difficult diminution of the will.  In your case of smoking, you may have had trouble with will power, but you were always free on some abstract level to quit.

Hugh: Do you believe there is something in addition to brain function that makes free will possible? It sounds as if you are speaking of free will as an expression of some other reality than the biochemistry of the brain.

 Susan: No, it's just an abstract illusion I like to believe in.

Hugh: I love that response. Picture me laughing even as I am writing to you now.   Well, let's move on to the final question: How has our study of consciousness affected you?

Susan: In so many ways!  I now walk around trying to be conscious of my consciousness.  All the kinds of thoughts Susan Blackmore talks about have occurred to me (conversations with people, plans for tomorrow, awareness of pain, etc.) as well as moments of quiet (no thoughts, but not exactly "abiding tranquility" either).  The idea of abiding tranquility appeals to me a great deal because I think it is one of the ways one might feel more in tune with or in unity with the universe.  I am beginning to think of consciousness as a multi-layered entity because there can be different levels of electrical activity (alpha brain waves as well as other types of waves), different levels of metabolic activity (the unconscious person being at the lowest level) and different thought patterns (thoughts versus no thoughts).  Because this is a hard problem to study, I will continue to read about consciousness with a new perspective on brain functioning, one which I owe mostly to you and your persistent questioning.  I myself have another question:  Is it not possible that Susan Blackmore's idea about how all of consciousness is an illusion an illusion as well?

Hugh: I admire Susan Blackmore. because she seems to me to be honest broker in the debate over consciousness. She has her own conclusions, of course, but she is exceptionally able to entertain opposing ideas. I think this mutes any charge that she may be succumbing to her own illusion. I feel as you do about our journey with our students through the mind and brain.  It has left me literally wandering aimlessly about.  When I think consciousness is an illusion, I seem to be trying to make myself disappear; when I think consciousness is a fundamental aspect of universe, I feel myself to be the grass waving in the wind. My final thought is that the only meaning is existence itself, illusion or no illusion.

Susan: I agree that "the only meaning is existence" and no matter how hard I try to think of all this as an illusion, my root canal reminds me otherwise.

Brain and Music

For additional information: 

https://www.urmc.rochester.edu/news/story/5127/patient-plays-saxophone-while-surgeons-remove-brain-tumor.aspx

http://www.npr.org/sections/health-shots/2017/08/25/545710598/this-music-teacher-played-his-saxophone-while-in-brain-surgery

Debate on Consciousness and Information Theory

 

 

John Searle: Download Can Information Theory Explain Consciousness

Excchange between Koch and Searle: Download Can a Photodiode Be Conscious

Nozick: the experience machine

Download Exper_machine_nozick

Henrik Ehrsson's Out-of-Body Experiments

Below are an article and a video on Ehrsson's out-of-body experiments.

Download Guterstam_ehrsson_2012

 

Meditation and Addiction

There is evidence that meditation can become addictive, especially when the intention is to escape everyday life. In particular, the feeling of bliss that some experience during meditation can be addictive and can cause ‘craving’.  That feeling of bliss would qualify, I think, as an hallucination.  (Interestingly enough, meditation is also sometimes used as a technique for ameliorating other kinds of addiction.)  It may be that when meditation takes place within a form of life, say that of a zen monastery, where the everyday life of an individual makes meditation not an escape but rather a ‘deep practice’ that reflects other daily practices that are consonant with it, 'craving' does not occur.

What it means to be conscious . . .

What it means to be conscious is that the world is meaningful to us.  Consciousness is as little able to be found in the brain as is the value of a precious family keepsake to be found in its physical construction. Meaning is what the brain does in its interaction with the external world. When we are aware, when there is something it is like to be us, when the world is accessible to us, there exists a meaningful relationship between our neural activity and the outside world.  Even in its most elementary openings, meaning is present.  Of course, there is some neural correlate for this meaning-making, but  meaning itself is not contained in this neural correlate. Rather, the meaning is present only in the activity of our full bodied, exploratory interaction with the world.  Dreaming, which seems to be an experience that brain originates on its own, is founded upon our interaction with the external world.  When we dream, it is as though we are seeking that original foundation.   That is why we ask what a dream means, not in terms of the dream itself, but in terms of the life we live when we are awake. It is as if dreaming is a kind of searching for something that is missing, our presence in the world.   

Comments on Wittgenstein's PHILOSOPHICAL INVESTIGATIONS: journal 21-25: Not a something, but not a nothing

21. What do we mean when we call something private? It may mean something that I have chosen not to speak of or it may mean something of which I claim ownership as a product of my physical or intellectual work or it may mean something that only I can know.  It is only the third of these senses that Wittgenstein questions:

 In what sense are my sensations private? Well, only I can know whether I am really in pain; another person can only surmise it. -- in one way this is false, and in another nonsense.  If we are using the word "know" as it is normally used (and how else are we to use it?), then other people very often know I'm in pain. -- Yes, but all the same, not with the certainty with which I know it myself! -- It can't be said of me at all (except perhaps as a joke) that I know I'm in pain.  What is it supposed to mean -- except perhaps that I am in pain? (PI 246)

The sentence "Sensations are private" is comparable to "One plays patience by oneself." (PI 248)

 What can it mean to play patience by oneself but to play patience?  What can it mean that sensations are private but that there are sensations?

 

22. What then are sensations?

 "And yet you again and again reach the conclusion that the sensation itself is a Nothing." -- Not at all. It's not a Something, but not a Nothing either! The conclusion was only that a Nothing would render the same service as a Something about which nothing could be said.  We've only rejected the grammar which tends to force itself on us here. (PI 293)

 There is a temptation here to use the phrase "a Something, but not a Nothing" as though referring denotatively to sensation. But Wittgenstein makes clear that he is talking here specifically about the "service" that such phrases as "not a Nothing" and "a something about which nothing can be said" to perform.  What service do such phrases serve? They serve to draw the line between what can be spoken of and what cannot. It is necessary to reject the grammar which tends to force a denotative sense on us. As denotative phrases, ‘Not A Something’ and ‘Not a Nothing’ cancel out. And yet, we would make it into a something. Just so language bewitches us. This way leads to mysticism. 

 23. Can we use "private" as equivalent with "that which cannot be said" as pertains to experience or sensation?  Wittgenstein himself never himself does.  And if we did, it would serve no purpose. The word "my" has meaning only in what can be talked about and what is therefore potentially accessible to others.

 "Another person can't have my pain." -- My pains -- what pains are they? . . . In so far as it makes sense to say that my pain is the same as his, it is also possible for us both to have the same pain. (PI 253).

 24. As Wittgenstein says in his discussion of the 'Beetle in the Box', "If we construe the grammar of the expression of sensation on the model of 'object and name', the object drops out of consideration as irrelevant" (PI 293). It does not belong to the language-game at all. Can 'sensation' be construed otherwise than on the model of 'object and name'? Of course.  It acquires meaning by its use in what it is our shared form of life. When you say "I have a toothache", I understand what you mean, not because "toothache" denotes something we can both privately observe in our experience and then conclude our experiences are similar -- rather, that the possibility of recognizing my toothache as a toothache in the first place depends upon a form of life in which what I call a toothache is what everyone else calls a toothache.  That is the language-game!

25. It is certainly true that I cannot be conscious of your pain as you are. This is to say no more than you are in pain and I am not. This fact, however, does not imply that your pain is thereby private such that your experience is essentially hidden from me. Your experience of pain is hidden from me only if you choose to hide it. 

 

 

 

 

 

 

 

The Problem of Meaning in Neuroscience

Neural activity has no meaning except in the context of our projects and activities. Of itself brain function is as meaningless as the fall of rain or the tides of the sea or the rotation of the earth apart from our witness. When something in the biochemistry of the brain changes and leaves a person impaired, the meaning of that impairment is founded upon the life denied, though human projects are such that impairment itself is often experienced not as tragic or even debilitating but as occasion for courage and love. The meaning of life lies not in the circuits of the brain but in forms of life in which we participate and in the language we use. It is a mistake to believe that such words as love, envy, or courage must point to something other than the structure of our activities.  What we hear when we speak of soul or the meaning of life is the poetry and music of our lives. What is most astonishing is that there is any meaning at all. That the meaning of life dies with us testifies to that meaning. Consciousness can not be found in the brain because apart from our language and our projects consciousness is nothing but a wind that is not even that.   

 

Stroke of Insight

 

Oliver Sacks' Footnote to "The Lost Mariner"

Kosakov’s Syndrome

“Gross disturbances of the organization of impressions of events and their sequence in time can always be observed in such patients,” he wrote. “In consequence, they lose their integral experience of time and begin to live in a world of isolated impressions.” -- Luria

Footnote

Further, there may be a profound retrograde amnesia in such cases. My colleague Dr. Leon Protass tells me of such a case seen by him recently, in which the patient, a highly intelligent man, was unable for some hours to remember his wife or children, to remember that he had a wife or children. In effect, he lost thirty years of his life—though, fortunately, for only a few hours. Recovery from such attacks is prompt and complete—yet they are, in a sense, the most horrifying of "little strokes" in their power absolutely to annul or obliterate decades of richly lived, richly achieving, richly memoried life. The horror, typically, is only felt by others—the patient, unaware, amnesiac for his amnesia, may continue what he is doing, quite unconcerned, and only discover later that he lost not only a day (as is common with ordinary alcoholic"blackouts"), but half a lifetime, and never knew it. The fact that one can lose the greater part of a lifetime has peculiar, uncanny horror.

There could be only one thing worse—and that would be to lose one's entire lifetime. My friend Dr. Isabelle Rapin, author of Children with Brain Dysfunction: Neurology, Cognition, Language, and Behavior, tells me that very rarely, in consequence of certain brain tumors or degenerative diseases, children may develop a severe Korsakov's syndrome. If this happens, it has been thought, they risk losing their childhood and even their infancy from a retrograde amnesia which may extend back to birth. Such children may not only become as helpless as newborns but may also become deeply "autistic" as they lose and forget all human relationships, even the most elemental—the memory of mother love.

In adulthood, life, higher life, may be brought to a premature end by strokes, senility, brain injuries, etc., but there usually remains the consciousness of life lived, of one's past. This is usually felt as a sort of compensation: "At least I lived fully, tasting life to the full, before I was brain-injured, stricken, etc." This sense of "the life lived before," which may be either a consolation or a torment, is precisely what is taken away in retrograde amnesia. The "final amnesia, the one that can erase a whole life" that Buñuel speaks of may occur, perhaps, in a terminal dementia, but not, in my experience, suddenly, in consequence of a stroke. But there is a different, yet comparable, sort of amnesia, which can occur suddenly—different in that it is not "global" but "modality-specific."

Thus, in one patient under my care, a sudden thrombosis in the posterior circulation of the brain caused the immediate death of the visual parts of the brain. Forthwith this patient became completely blind—but did not know it. He looked blind—but he made no complaints. Questioning and testing showed, beyond doubt, that not only was he centrally or "cortically" blind, but he had lost all visual images and memories, lost them totally—yet had no sense of any loss. Indeed, he had lost the very idea of "seeing"—and was not only unable to describe anything visually, but bewildered when I used words such as "seeing" and "light." He had become, in essence, a nonvisual being. His entire lifetime of seeing, of visuality, had, in effect, been stolen. His whole visual life had, indeed, been erased—and erased permanently in the instant of his stroke. Such a visual amnesia, and (so to speak) blindness to the blindness, amnesia for the amnesia, is in effect a "total" Korsakov's, confined to visuality.

A still more limited, but nonetheless total, amnesia may be displayed with regard to particular forms of perception. Thus, in one patient whose history I have already described ("The Man Who Mistook his Wife for a Hat," London Review of Books, vol. 5, no. 9, May 1983), there was an absolute "prosopagnosia," or agnosia for faces. This patient was not only unable to recognize faces, but unable to imagine or remember any faces—he had indeed lost the very idea of a "face," as my more afflicted patient had lost the very idea of "seeing" or "light." Such syndromes were described by Anton
in the 1890s. But the implication of these syndromes—Korsakov's and Anton's—what they entail and must entail for the "world," the lives, the identities, of affected patients, has been scarcely touched on even to this day.

Oliver Sacks: A Neurology of Identity

The patient’s essential being is very relevant in the higher reaches of neurology, and in psychology; for here the patient’s personhood is essentially involved, and the study of disease and of identity cannot be disjoined. Such disorders, and their depiction and study, indeed entail a new discipline, which we may call the ‘neurology of identity’, for it deals with the neural foundations of the self, the age-old problem of mind and brain. It is possible that there must, of necessity, be a gulf, a gulf of category, between the psychical and the physical; but studies and stories pertaining simultaneously and inseparably to both—and it is these which especially fascinate me, and which (on the whole) I present here—may nonetheless serve to bring them nearer, to bring us to the very intersection of mechanism and life, to the relation of physiological processes to biography.

---from Oliver Sack's Introduction to The Man Who Mistook His Wife For A Hat

The end of the free will debate

The free will vs. determinism debate derives its relevance from dualistic thinking, i.e. that our conscious self is not the one driving the boat, as if there were on the one hand a consciousness that is ignorant of the source of its choices and on the other a brain that is purely mechanical and unconsciously drives our decisions. That argument presupposes that consciousness is something other than the natural unfolding of brain function. This notion of unfolding yields an organic and coherent understanding of how we make decisions. Consciousness is a dimension of a dynamic system, one that allows for self-correction and support for an organism’s fundamental integrity. That the dynamic system is deterministic says no more than that the unfolding of the brain is a natural process that realizes itself in awareness. It is one process, not two. How could it be otherwise? To move at last beyond such dualistic thinking allows us further to contemplate ourselves as an unfolding within a universal process -- as a wave that moves always at one with itself and the sea of which it is an expression.

Colin Martz: The Case for Earlier Neuroscience Education, Plus Resources for Educators

I had the very great pleasure to teach Colin while he was in high school. A more thoughtful student would be hard to find. He is now studying neuroscience at Duke. Below is an excerpt from Colin's paper which can be read in its entirety at the following link: http://www.hastac.org/blogs/cmartz/case-earlier-neuroscience-education-plus-resources-educators-who-believe-me. You will find there a very helpful list of resources for educators who want to put Colin's ideas into practice.

To begin, I would like to describe my personal relationship with science education from the 6th grade to the 12th grade. Now, bear in mind that I was fortunate enough to attend a well-funded college preparatory school for these years, so my case is far from representative of the average American education. Nevertheless, for the majority of my high school career, I wanted nothing to do with science. I derived little pleasure from balancing chemical equations or learning about photosynthesis, and I dreaded the introduction of each new topic in my calculus class. On the other hand, I loved my English classes, largely because the readings and discussions they entailed shed light on just how rich, diverse and nuanced peoples thoughts and experiences could be. Science classes were always so abstract and detached from everything I learned through my own experiences in the world. I had nothing tangible to connect each new concept to, and as a result I felt like I was building a whole new world that operated by a series of seemingly arbitrary rules.

Then, during the second semester of my senior year, a teacher introduced me to Roger Sperrys famous research with split-brain patients (see also: http://nobelprize.org/educational/medicine/split-brain/index.html). It was that experience that demonstrated to me how cool science could be; it just had to be directed at something more human and immediately relevant for me to appreciate it. I set up a senior project with that teacher in the form of a seminar about what neuroscience and philosophy of mind, and now in my junior year of college I can say that my fascination with the brain has only grown since. What I learned that year was that neuroscience has infinite applicability. That is, the study of the brain is relevant to literally anything that involves people, and this because everything we do and think depends on that blob of finely folded tissue that resides in our skulls. Neuroscience has something to say about sex, drugs, and rock and rolland thats just the beginning. Kids that love sports are likely to find information about how the brain controls and interfaces with the body interesting. Those who like their foreign language classes might be captivated by the neuroscience of human language. Id also wager that many kids would be interested in learning about their own development and what they can do to get the most out of their brains. This discussion gets into nutrition and the brain, which of course can naturally connect to the sense of taste and how food stimuli are transduced into sensations by our brains. The point here is that given the central roles the brain plays in our lives, it isnt hard to connect kids interests to topics in neuroscience. This, I think, is the key to successful science teaching: instructors have to make science immediately relevant to their students lives.

Despite the potential the neuroscience holds to serve as a powerful tool for introducing young people to scientific principles and for generating interest in careers in science, it typically isnt taught before college. This needs to change. The traditional justification for delaying its presentation is that students should have a solid foundation in the more fundamental natural sciencesphysics, chemistry and biologybefore they begin to study the brain because a sophisticated understanding of its function (and dysfunction) draws from all of these disciplines. This is true, but for just that: a sophisticated understanding. The purpose of introducing neuroscience at the middle and high school levels (and perhaps earlier still) is not to confer a detailed understanding of brain. This should be reserved for university level coursework. Instead, the end of these neuroscience lessons is simply to demonstrate to children that science need not be so abstract and detached from their own experience that it becomes boring and onerous.

Note that I am not suggesting that neuroscience topics should supplant traditional physics, chemistry and biology classes. However, they should inform and enrich these subjects. Physics could be brought to life by considering reaction times and the speed of nerve conduction in addition to the tired old problems about trains careening toward one another. Neurotransmitters activities could be discussed alongside the traditional treatment of acid-base chemistry, and biology, of course, is the easiest of these canonical subjects when it comes to integrating exciting information about the brain with core coursework. I believe that by applying abstract principles from more basic natural sciences to concrete situations in neuroscience and behavior, science teachers around the country could humanize science and dissolve aversions and anxieties students associate with the subject.

Excerpt from Wittgenstein's Notes for Lectures on "Private Experience" and "Sense Data"

"I say 'I have toothache' because I feel it" contrasts this case with, say, the case of acting on the stage, but can't explain what 'having toothache' means because having toothache = feeling toothache, and the explanation would come to: "I say I have it because I have it" = I say I have it because it is true = I say I have it because I don't lie. One wishes to say: In order to be able to say that I have toothache I don't observe my behavior, say in the mirror. And this is correct, but it doesn'tfollow that you describe an observation of any other kind. Moaning is not the description of an observation.That is, you can't be said to derive your expression from what you observe. Just as you can't be said to derive the word 'green' from your visual impression but only from a sample. Now against this one is inclined to say: "Surely if I call a color green I don't just say that word, but the word comes in a particular way," or "if I say 'I have toothache' I don't just use this phrase but it must come in a particular way!" Now this means nothing, for, if you like, it always comes in a particular way.

"But surely seeing and saying something can't be all!" Here we make the confusion that there is still an object we haven't mentioned. You imagine that there is a pure seeing and saying, and one + something else. Therefore you imagine all distinctions to be made as between a, a + b, a + c, etc. The idea of this addition is mostly derived from consideration of our bodily organs. All that ought to interest you is whether I make all the distinctions that you make: whether, e.g., I distinguish between cheating and telling the truth.-"There is something else!"-"There is nothing else!"- "But what else is there?"-"Well, this / !" "But surely I know that I am not a mere automaton!"-What would it be like if I were?-"How is it that I can't imagine myself not experiencing seeing, hearing etc.?"-We constantly confuse and change about the commonsense use and the metaphysical use.

"I know that I see."-

"I see."-you seem to read this off some fact; as though you said: "There is a chair in this corner." "But if in an experiment, e.g., I say 'I see,' why do I say so? surely because I see!" It is as though our expressions of personal experience needn't even spring from regularly recurrent inner experiences but just from something.

Confusion of description and samples. The idea of the 'realm of consciousness.'

Brian Lewis Saunders: representations of experience

PAIN

For much more, go to: http://bryanlewissaunders.org/spseries/
Click on images for an in depth look.

The Debate Over Mirror Neurons: Ramachandran, Gernsbacher et alii

Against:

Download What the myth of mirror neurons gets wrong about the human brain

For: Ramachandran

Against: Gernsbacher

Mirror Neurons in Humans? from Morton Ann Gernsbacher on Vimeo.

David Chalmers on Emergence

 

Here is an online paper by Chalmers that expands upon the video:

http://consc.net/papers/emergence.pdf

In the beginning was the word

For consciousness to be what it is the brain must be able to take its own activity as an object. The brain must have a meta-mechanism by which it partially re-represents its interaction with its environment. This re-representation creates a feedback loop to the original activity. It is this feedback loop that makes possible the experience, if not the reality, of free will. The re-representation is accomplished through language, such that if there is no language there is no consciousness -- as the split-brain research reveals. Language in its re-representation creates a self to whom the activity of the brain belongs. It is that creation of the self that makes us feel that there is something it is like to be me because that is the story that the brain tells itself. Consciousness itself is that story. There may also a proto-consciousness, a potentiality or readiness state, anticipatory of the word, a state of simple synchrony between the original brain activity and its re-representation.

Emergence

If we apply Schrodinger's concept of objectification to emergence theory, the consequence profoundly shifts the nature of the problem that emergence was intended to solve.  Emergence always occurs to an observer and the observer therefore must be included in the matrix of the event. Once the observer is included, the phenomen of emergence is at once more complex and less magical.  My suspicion is that emergence theory has become a backdoor for spiritualists.

Museum of Scientifically Accurate Fabric Brain Art

http://harbaugh.uoregon.edu/Brain/index.htm

Where Ideas Come from

http://podcasts.theatlantic.com/2008/07/where-ideas-come-from.php

David Eagleman Lab Website

http://neuro.bcm.edu/eagleman/

Ten Unsolved Mysteries of the Brain by David Eagleman

Of all the objects in the universe, the human brain is the most complex: There are as many
neurons in the brain as there are stars in the Milky Way galaxy. So it is no surprise that,
despite the glow from recent advances in the science of the brain and mind, we still find
ourselves squinting in the dark somewhat. But we are at least beginning to grasp the
crucial mysteries of neuroscience and starting to make headway in addressing them.
Even partial answers to these 10 questions could restructure our understanding of the
roughly three-pound mass of gray and white matter that defines who we are.

1. How is information coded in neural activity?

Neurons, the specialized cells of the brain, can produce brief spikes of voltage in their
outer membranes. These electrical pulses travel along specialized extensions called axons
to cause the release of chemical signals elsewhere in the brain. The binary, all-or nothing
spikes appear to carry information about the world: What do I see? Am I hungry? Which
way should I turn? But what is the code of these millisecond bits of voltage? Spikes may
mean different things at different places and times in the brain. In parts of the central
nervous system (the brain and spinal cord), the rate of spiking often correlates with clearly
definable external features, like the presence of a color or a face.

In the peripheral nervous system, more spikes indicates more heat, a louder sound, or a
stronger muscle contraction. As we delve deeper into the brain, however, we find populations
of neurons involved in more complex phenomena, like reminiscence, value judgments,
simulation of possible futures, the desire for a mate, and so on—and here the signals
become difficult to decrypt. The challenge is something like popping the cover off a
computer, measuring a few transistors chattering between high and low voltage, and trying
to guess the content of the Web page being surfed.

It is likely that mental information is stored not in single cells but in populations of cells
and patterns of their activity. However, it is currently not clear how to know which
neurons belong to a particular group; worse still, current technologies (like sticking fine
electrodes directly into the brain) are not well suited to measuring several thousand
neurons at once. Nor is it simple to monitor the connections of even one neuron: A
typical neuron in the cortex receives input from some 10,000 other neurons.
Although traveling bursts of voltage can carry signals across the brain quickly, those
electrical spikes may not be the only—or even the main—way that information is carried
in nervous systems. Forward-looking studies are examining other possible information
couriers: glial cells (poorly understood brain cells that are 10 times as common as
neurons), other kinds of signaling mechanisms between cells (such as newly discovered
gases and peptides), and the biochemical cascades that take place inside cells.

2. How are memories stored and retrieved?

When you learn a new fact, like someone’s name, there are physical changes in the
structure of your brain. But we don’t yet comprehend exactly what those changes are,
how they are orchestrated across vast seas of synapses and neurons, how they embody
knowledge, or how they are read out decades later for retrieval.

One complication is that there are many kinds of memories. The brain seems to
distinguish short-term memory (remembering a phone number just long enough to dial
it) from long-term memory (what you did on your last birthday). Within long-term
memory, declarative memories (like names and facts) are distinct from nondeclarative
memories (riding a bicycle, being affected by a subliminal message), and within these
general categories are numerous subtypes. Different brain structures seem to support
different kinds of learning and memory; brain damage can lead to the loss of one type
without disturbing the others.

Nonetheless, similar molecular mechanisms may be at work in these memory types.
Almost all theories of memory propose that memory storage depends on synapses, the
tiny connections between brain cells. When two cells are active at the same time, the
connection between them strengthens; when they are not active at the same time, the
connection weakens. Out of such synaptic changes emerges an association. Experience
can, for example, fortify the connections between the smell of coffee, its taste, its color,
and the feel of its warmth. Since the populations of neurons connected with each of
these sensations are typically activated at the same time, the connections between them
can cause all the sensory associations of coffee to be triggered by the smell alone.
But looking only at associations—and strengthened connections between neurons—may
not be enough to explain memory. The great secret of memory is that it mostly encodes
the relationships between things more than the details of the things themselves. When
you memorize a melody, you encode the relationships between the notes, not the notes
per se, which is why you can easily sing the song in a different key.

Memory retrieval is even more mysterious than storage. When I ask if you know Alex
Ritchie, the answer is immediately obvious to you, and there is no good theory to
explain how memory retrieval can happen so quickly. Moreover, the act of retrieval can
destabilize the memory. When you recall a past event, the memory becomes temporarily
susceptible to erasure. Some intriguing recent experiments show it is possible to
chemically block memories from reforming during that window, suggesting new ethical
questions that require careful consideration.

3. What does the baseline activity in the brain represent?

Neuroscientists have mostly studied changes in brain activity that correlate with stimuli
we can present in the laboratory, such as a picture, a touch, or a sound. But the activity
of the brain at rest—its “baseline” activity—may prove to be the most important aspect
of our mental lives. The awake, resting brain uses 20 percent of the body’s total oxygen,
even though it makes up only 2 percent of the body’s mass. Some of the baseline
activity may represent the brain restructuring knowledge in the background, simulating
future states and events, or manipulating memories. Most things we care about—
reminiscences, emotions, drives, plans, and so on—can occur with no external stimulus
and no overt output that can be measured.

One clue about baseline activity comes from neuroimaging experiments, which show
that activity decreases in some brain areas just before a person performs a goal-directed
task. The areas that decrease are the same regardless of the details of the task, hinting
that these areas may run baseline programs during downtime, much as your computer
might run a disk-defragmenting program only while the resources are not needed
elsewhere.

In the traditional view of perception, information from the outside world pours into the
senses, works its way through the brain, and makes itself consciously seen, heard, and
felt. But many scientists are coming to think that sensory input may merely revise
ongoing internal activity in the brain. Note, for example, that sensory input is
superfluous for perception: When your eyes are closed during dreaming, you still enjoy
rich visual experience. The awake state may be essentially the same as the dreaming
state, only partially anchored by external stimuli. In this view, your conscious life is an
awake dream.

The awake state may be essentially the same as the dreaming state. In this view, your
conscious life is an awake dream.

4. How do brains simulate the future?

When a fire chief encounters a new blaze, he quickly makes predictions about how to
best position his men. Running such simulations of the future—without the risk and
expense of actually attempting them—allows “our hypotheses to die in our stead,” as
philosopher Karl Popper put it. For this reason, the emulation of possible futures is one
of the key businesses that intelligent brains invest in.

Yet we know little about how the brain’s future simulator works because traditional
neuroscience technologies are best suited for correlating brain activity with explicit
behaviors, not mental emulations. One idea suggests that the brain’s resources are
devoted not only to processing stimuli and reacting to them (watching a ball come at
you) but also to constructing an internal model of that outside world and extracting rules
for how things tend to behave (knowing how balls move through the air). Internal
models may play a role not only in motor acts, like catching, but also in perception. For
example, vision draws on significant amounts of information in the brain, not just on
input from the retina. Many neuroscientists have suggested over the past few decades
that perception arises not simply by building up bits of data through a hierarchy but
rather by matching incoming sensory data against internally generated expectations.
But how does a system learn to make good predictions about the world? It may be that
memory exists only for this purpose. This is not a new idea: Two millennia ago, Aristotle
and Galen emphasized memory as a tool in making successful predictions for the future.
Even your memories about your life may come to be understood as a special subtype of
emulation, one that is pinned down and thus likely to flow in a certain direction.

5. What are emotions?

We often talk about brains as information-processing systems, but any account of the
brain that lacks an account of emotions, motivations, fears, and hopes is incomplete.
Emotions are measurable physical responses to salient stimuli: the increased heartbeat
and perspiration that accompany fear, the freezing response of a rat in the presence of
a cat, or the extra muscle tension that accompanies anger. Feelings, on the other hand,
are the subjective experiences that sometimes accompany these processes: the
sensations of happiness, envy, sadness, and so on. Emotions seem to employ largely
unconscious machinery—for example, brain areas involved in emotion will respond to
angry faces that are briefly presented and then rapidly masked, even when subjects are
unaware of having seen the face. Across cultures the expression of basic emotions is
remarkably similar, and as Darwin observed, it is also similar across all mammals. There
are even strong similarities in physiological responses among humans, reptiles, and birds
when showing fear, anger, or parental love.

Modern views propose that emotions are brain states that quickly assign value to
outcomes and provide a simple plan of action. Thus, emotion can be viewed as a type of
computation, a rapid, automatic summary that initiates appropriate actions. When a
bear is galloping toward you, the rising fear directs your brain to do the right things
(determining an escape route) instead of all the other things it could be doing (rounding
out your grocery list). When it comes to perception, you can spot an object more quickly
if it is, say, a spider rather than a roll of tape. In the realm of memory, emotional events
are laid down differently by a parallel memory system involving a brain area called the
amygdala.

One goal of emotional neuroscience is to understand the nature of the many disorders
of emotion, depression being the most common and costly. Impulsive aggression and
violence are also thought to be consequences of faulty emotion regulation.

6. What is intelligence?

Intelligence comes in many forms, but it is not known what intelligence—in any of its
guises—means biologically. How do billions of neurons work together to manipulate
knowledge, simulate novel situations, and erase inconsequential information? What
happens when two concepts “fit” together and you suddenly see a solution to a
problem? What happens in your brain when it suddenly dawns on you that the killer in
the movie is actually the unsuspected wife? Do intelligent people store knowledge in a
way that is more distilled, more varied, or more easily retrievable?
We all grew up with the near-future promise of smart robots, but today we have little
better than the Roomba robotic vacuum cleaner. What went wrong? There are two
camps for explaining the weak performance of artificial intelligence: Either we do not
know enough of the fundamental principles of brain function, or we have not simulated
enough neurons working together. If the latter is true, that’s good news: Computation
gets cheaper and faster each year, so we should not be far from enjoying life with
Asimovian robots who can effectively tend our households. Yet most neuroscientists
recognize how distant we are from that dream. Currently, our robots are little more
intelligent than sea slugs, and even after decades of clever research, they can barely
distinguish figures from a background at the skill level of an infant.
Recent experiments explore the possible relationship of intelligence to the capacity of
short-term memory, the ability to quickly resolve cognitive conflict, or the ability to store
stronger associations between facts; the results are not yet conclusive. Many other
possibilities—better restructuring of stored information, more parallel processing, or
superior emulation of possible futures—have not yet been probed by experiments.
Intelligence may not be underpinned by a single mechanism or a single neural area.
Whatever intelligence is, it lies at the heart of what is special about Homo sapiens.
Other species are hardwired to solve particular problems, while our ability to abstract
allows us to solve an open-ended series of problems. This means that studies of
intelligence in mice and monkeys may be barking up the wrong family tree.

7. How is time represented in the brain?

Hundred-yard dashes begin with a gunshot rather than a strobe light because your brain
can react more quickly to a bang than to a flash. Yet as soon as we get outside the
realm of motor reactions and into the realm of perception (what you report that you saw
and heard), the story changes. When it comes to awareness, the brain goes through a
good deal of trouble to synchronize incoming signals that are processed at very different
speeds.

For example, snap your fingers in front of you. Although your auditory system processes
information about the snap about 30 milliseconds faster than your visual system, the
sight of your fingers and the sound of the snap seem simultaneous. Your brain is
employing fancy editing tricks to make simultaneous events in the world feel
simultaneous to you, even when the different senses processing the information would
individually swear otherwise.

For a simple example of how your brain plays tricks with time, look in the mirror at your
left eye. Now shift your gaze to your right eye. Your eye movements take time, of
course, but you do not see your eyes move. It is as if the world instantly made the
transition from one view to the next. What happened to that little gap in time? For that
matter, what happens to the 80 milliseconds of darkness you should see every time you
blink your eyes? Bottom line: Your notion of the smooth passage of time is a
construction of the brain. Clarifying the picture of how the brain normally solves timing
problems should give insight into what happens when temporal calibration goes wrong,
as may happen in the brains of people with dyslexia. Sensory inputs that are out of sync
also contribute to the risk of falls in elderly patients.

We grew up with the near-future promise of smart robots, but today we have little
better than the Roomba robotic vacuum cleaner. What went wrong?

8. Why do brains sleep and dream?

One of the most astonishing aspects of our lives is that we spend a third of our time in
the strange world of sleep. Newborn babies spend about twice that. It is inordinately
difficult to remain awake for more than a full day-night cycle. In humans, continuous
wakefulness of the nervous system results in mental derangement; rats deprived of
sleep for 10 days die. All mammals sleep, reptiles and birds sleep, and voluntary
breathers like dolphins sleep with one brain hemisphere dormant at a time. The
evolutionary trend is clear, but the function of sleep is not.

The universality of sleep, even though it comes at the cost of time and leaves the
sleeper relatively defenseless, suggests a deep importance. There is no universally
agreed-upon answer, but there are at least three popular (and nonexclusive) guesses.
The first is that sleep is restorative, saving and replenishing the body’s energy stores.
However, the high neural activity during sleep suggests there is more to the story. A
second theory proposes that sleep allows the brain to run simulations of fighting,
problem solving, and other key actions before testing them out in the real world. A third
theory—the one that enjoys the most evidence—is that sleep plays a critical role in
learning and consolidating memories and in forgetting inconsequential details. In other
words, sleep allows the brain to store away the important stuff and take out the neural
trash.

Recently, the spotlight has focused on REM sleep as the most important phase for
locking memories into long-term encoding. In one study, rats were trained to scurry
around a track for a food reward. The researchers recorded activity in the neurons
known as place cells, which showed distinct patterns of activity depending upon the rats’
location on the track. Later, while the rats dropped off into REM sleep, the recordings
continued. During this sleep, the rats’ place cells often repeated the exact same pattern
of activity that was seen when the animals ran. The correlation was so close, the
researchers claimed, that as the animal “dreamed,” they could reconstruct where it
would be on the track if it had been awake—and whether the animal was dreaming of
running or standing still. The emerging idea is that information replayed during sleep
might determine which events we remember later. Sleep, in this view, is akin to an offline
practice session. In several recent experiments, human subjects performing difficult
tasks improved their scores between sessions on consecutive days, but not between
sessions on the same day, implicating sleep in the learning process.
Understanding how sleeping and dreaming are changed by trauma, drugs, and
disease—and how we might modulate our need for sleep—is a rich field to harvest for
future clues.

9. How do the specialized systems of the brain integrate with one another?

To the naked eye, no part of the brain’s surface looks terribly different from any other
part. But when we measure activity, we find that different types of information lurk in
each region of the neural territory. Within vision, for example, separate areas process
motion, edges, faces, and colors. The territory of the adult brain is as fractured as a
map of the countries of the world.

Now that neuroscientists have a reasonable idea of how that territory is divided, we find
ourselves looking at a strange assortment of brain networks involved with smell, hunger,
pain, goal setting, temperature, prediction, and hundreds of other tasks. Despite their
disparate functions, these systems seem to work together seamlessly. There are almost
no good ideas about how this occurs.

Nor is it understood how the brain coordinates its systems so rapidly. The slow speed of
spikes (they travel about one foot per second in axons that lack the insulating sheathing
called myelin) is one hundred-millionth the speed of signal transmission in digital
computers. Yet a human can recognize a friend almost instantaneously, while digital
computers are slow—and usually unsuccessful—at face recognition. How can an organ
with such slow parts operate so quickly? The usual answer is that the brain is a parallel
processor, running many operations at the same time. This is almost certainly true, but
what slows down parallel-processing digital computers is the next stage of operations,
where results need to be compared and decided upon. Brains are amazingly fast at this.
So while the brain’s ability to do parallel processing is impressive, its ability to rapidly
synthesize those parallel processes into a single, behavior-guiding output is at least as
significant. An animal running must go left or right around a tree; it cannot do both.
There is no special anatomical location in the brain where information from all the
different systems converges; rather, the specialized areas all interconnect with one
another, forming a network of parallel and recurring links. Somehow, our integrated
image of the world emerges from this complex labyrinthine network of brain structures.
Surprisingly little study has been done on large, loopy networks like the ones in the
brain—probably in part because it is easier to think about brains as tidy assembly lines
than as dynamic networks.

10. What is consciousness?

Think back to your first kiss. The experience of it may pop into your head instantly.
Where was that memory before you became conscious of it? How was it stored in your
brain before and after it came into consciousness? What is the difference between those
states

An explanation of consciousness is one of the major unsolved problems of modern
science. It may not turn out to be a single phenomenon; nonetheless, by way of a
preliminary target, let’s think of it as the thing that flickers on when you wake up in the
morning that was not there, in the exact same brain hardware, moments before.
Neuroscientists believe that consciousness emerges from the material stuff of the brain
primarily because even very small changes to your brain (say, by drugs or disease) can
powerfully alter your subjective experiences. The heart of the problem is that we do not
yet know how to engineer pieces and parts such that the resulting machine has the kind
of private subjective experience that you and I take for granted. If I give you all the
Tinkertoys in the world and tell you to hook them up so that they form a conscious
machine, good luck. We don’t have a theory yet of how to do this; we don’t even know
what the theory will look like.

One of the traditional challenges to consciousness research is studying it experimentally.
It is probable that at any moment some active neuronal processes correlate with
consciousness, while others do not. The first challenge is to determine the difference
between them. Some clever experiments are making at least a little headway. In one of
these, subjects see an image of a house in one eye and, simultaneously, an image of a
cow in the other. Instead of perceiving a house-cow mixture, people perceive only one
of them. Then, after some random amount of time, they will believe they’re seeing the
other, and they will continue to switch slowly back and forth. Yet nothing about the
visual stimulus changes; only the conscious experience changes. This test allows
investigators to probe which properties of neuronal activity correlate with the changes in
subjective experience.

The mechanisms underlying consciousness could reside at any of a variety of physical
levels: molecular, cellular, circuit, pathway, or some organizational level not yet
described. The mechanisms might also be a product of interactions between these
levels. One compelling but still speculative notion is that the massive feedback circuitry
of the brain is essential to the production of consciousness.
In the near term, scientists are working to identify the areas of the brain that correlate
with consciousness. Then comes the next step: understanding why they correlate. This
is the so-called hard problem of neuroscience, and it lies at the outer limit of what
material explanations will say about the experience of being human.

David Eagleman

Today I attended three lectures by David Eagleman on the following topics in neuroscience: the ten unsolved mysteries of the brain, synesthesia, and sleep.  All three were exccellent.  David is a 1989 graduate of Albuquerque Academy where I teach. I hope he will return to AA this year and discuss these and other issues in neuroscience with my students. Four books by David are due to be published in the coming months. For now you can find him on YOUTUBE. Here is one link: http://www.youtube.com/watch?v=j3M7sUm-0Rw

Mirror Neurons Update

Essay

Nature 454, 167-168 (10 July 2008) | doi:10.1038/454167a; Published online 9 July 2008

Behind the looking-glass

Antonio Damasio1 & Kaspar Meyer1

   1. Antonio Damasio and Kaspar Meyer are neuroscientists at the Brain and Creativity Institute of the University of Southern California, Los Angeles, USA.

To understand how mirror neurons help to interpret actions, we must delve into the networks in which these cells sit, say Antonio Damasio and Kaspar Meyer.
Behind the looking-glass

D. PARKINS

A remarkable discovery was made more than ten years ago: some neurons in the brains of macaques are active both when a monkey moves and when it sees a person move in a comparable way1. The lead researchers, Giacomo Rizzolatti and Vittorio Gallese, called the cells involved 'mirror neurons'. This evocative name, and the significant implications of the finding, led to a surge of scientific and public interest in these cells. But perhaps the name was too evocative for the finding's own good. It seems to have tempted people into thinking of these neurons as tiny, miraculous mirrors that allow us to understand each other, diverting attention from the search for how they work.

After mirror neurons were found in two main regions of macaque brains1, 2, corresponding results were found in human brain scans3. Researchers began to invoke mirror neurons to explain the fundamental task of how humans and other primates recognize the actions and, by extension, the intentions of others. Mirror-neuron activity is thought to generate a more-or-less explicit simulation of others' actions in the observer's brain. If this is the case, then simulation, rather than inference, would provide a deep understanding of those movements. Some have proposed that mirror neurons are a vital part of how infants first learn to imitate other people's actions; of why seeing a grimace can trigger empathetic feeling in a watcher; and even of how language is learned. Although simulation is unlikely to account entirely for how people understand what they see other people do, the identification of mirror neurons was an important step on the path to unpacking that process.

    Hearing a peanut being broken without seeing or feeling it triggers a whole neural network.

Unfortunately, the lack of a satisfactory explanation for how the simulation process occurs has allowed the notion to take hold — among the public and scientists alike — that mirror neurons accomplish mirroring on their own in some mysterious way.

Surely, if 'action understanding' is to occur by internal simulation, the process must enlist both motor and sensory systems in the brain. Mirror neurons cannot accomplish this task alone. Rather, they must be acted on by other structures; and, just as importantly but a fact generally neglected, mirror neurons must act on other structures.
Mutual support

Unravelling how mirror neurons work requires knowledge of the complex architecture in which these cells are embedded. A model of neural architecture proposed by one of us (A.D.)4 nearly 20 years ago may help with that. Impressive findings from mirror-neuron research at the single-cell level have added persuasive empirical support for this early model.

The model, originally called 'time-locked multimodal retroactivation', was derived during the 1980s from observations in patients with brain lesions. Some patients with damage in the anterior (higher-order) sectors of the temporal cortex, for example, could not recall complex memories that combine separate components of a specific event, such as a face, a name, an action or a place. These patients could not recognize close friends or relatives, nor could they picture unique events in time and place, such as their own wedding or the birth of a child. Yet they could easily imagine or recognize a picture of a non-specific wedding or a baby.

In other words, anterior damage did not preclude their retrieval of mental representations of objects, places or actions; but it did stop them recalling certain combinations of representations that signified a particular person or event. Only damage to posterior sectors of the cerebral cortex, near sensory and motor cortices, impaired access to separable memory components. Given what was already known about memory systems, this suggested that anterior sites held the key to some process needed to reconstruct, elsewhere, the parts that made up a complex memory.
Mind mapping

An idea for a brain architecture that could explain these findings was inspired by experimental neuroanatomy studies showing that, surprisingly, signals are conveyed within the brain in both forwards and backwards directions. For example, signals are obviously sent from the eye to the visual cortex and on to areas of higher-level processing in the brain. But these high-level areas also send signals back to the visual cortex, and even to the visual thalamus, below the level of the cortex5. The same forward–backward signalling arrangement was found for the hippocampus — a brain region involved in making factual memories6.

All this led to a model that posited the existence of 'convergence–divergence zones' (CDZs). These neural ensembles collect signals from separate sites, and signal back to those sites. When several signals converge on a CDZ, the ensemble creates an abstract record of the coincident activations — a memory trace, in other words. The model contained two broad types of CDZ. 'Local CDZs' were proposed to coordinate information within regions close to a sensory cortex, such as the visual cortex. These local hubs were proposed to converge on 'non-local CDZs' in higher-order sectors of the brain.

In this view, when a monkey breaks open a peanut7, local CDZs collect information about various sensory inputs, and feed these to a non-local CDZ that records the coincident information about the sound, sight and feel of this action. The CDZ does not hold all the details of this information; rather, it contains the potential to retroactivate the separate auditory, visual, tactile and motor sites, and thus reconstitute the original distributed set of memories and information. Imagine the CDZ as a repository of instructions for a book that must be printed by several different printers. Having the instructions alone will not get you the book, and the printers alone will not help either. You need both to get the final product.

In future, hearing a peanut being broken without seeing or feeling it triggers a series of events. First, it activates the auditory cortices and local auditory CDZ; second, it activates the non-local CDZ that previously collected the memory trace associated with this sound; third, it precipitates simultaneous signalling outwards from this non-local CDZ to all the local CDZs involved in the original event (motor, visual, auditory); fourth, it reactivates all or some of these sites. This leads to a more-or-less successful replay of the coincident set of separate brain activities that accompanied the monkey breaking open a peanut.

    The neurons are not so much like mirrors, after all. They are more like puppet masters, pulling the strings of various memories.

Looked at in this way, mirror neurons correspond to non-local CDZs. Their connections to other CDZs, and their ability to collect and distribute signals based on learned experience, allow the brain to reconstruct an action from only part of the story. A whole neural network underlies the understanding of action, rather than a single anatomical site or even a single cell. The monkey's comprehension of the sound of a cracking nut is not created just by mirror-neuron sites, but also by the nearly simultaneous triggering of widespread memories throughout the brain.

The neurons at the heart of this process, and at the heart of non-local CDZs, are not so much like mirrors, after all. They are more like puppet masters, pulling the strings of various memories.

Recent findings are in line with this view. Studies in humans and monkeys show that the neural network stimulated by watching an action goes beyond the original mirror-neuron sites; it encompasses more widespread sensorimotor cortices3, 8. Conversely, carrying out an action recruits sensory cortical areas even when subjects can neither see nor hear the actions they perform9. This lends further support to the notion that the neural description of an action goes far beyond its motor components. At least one other study has invoked the necessity of convergent signals into mirror-neuron areas to explain such observations10. The CDZ model, and our interpretation of mirror neurons, adds the aspect of divergence.
Neural networks

The CDZ framework allows us to see the role of mirror neurons more clearly. Cells in mirror-neuron areas do not themselves hold meaning, and they alone cannot carry out the internal simulation of an action. This runs counter to the understandable public misconception that mirror neurons alone 'mirror' action. Rather, mirror neurons induce widespread neural activity based on learned patterns of connectivity; these patterns generate internal simulation and establish the meaning of actions. Mirror neurons pull the strings, but the puppet itself is made of a large brain network.

The CDZ model was well received, but the lack of single-cell experiments providing direct evidence for this functional architecture has limited the application of the idea. The mirror-neuron evidence sits well alongside the model, and each seems to make more sense in light of the other. But this is not proof. The ultimate test of the convergence–divergence model, and its explanation of how mirror neurons do what they do, depends on the ability to record brain activity simultaneously from neurons in separate sites, and on probing the underlying connectivity between neural areas. Such goals are within reach, albeit technically difficult to achieve. In the meantime, bringing together mirror-neuron data and the CDZ model could guide future efforts to explain the relationship between what we see and what we do.

Top of page
References

   1. Gallese, V., Fadiga, L., Fogassi, L. & Rizzolatti, G. Brain 119, 593–609 (1996). | Article | PubMed | ISI |
   2. Fogassi, L., Gallese, V., Fadiga, L. & Rizzolatti, G. Soc. Neurosci. 24, abstr. 257.5 (1998).
   3. Buccino, G. et al. Eur. J. Neurosci. 13, 400–404 (2001). | Article | PubMed | ISI | ChemPort |
   4. Damasio, A. R. Cognition 33, 25–62 (1989). | Article | PubMed | ISI | ChemPort |
   5. Rockland, K. S. & Pandya, D. N. Brain Res. 212, 249–270 (1981). | Article | PubMed | ISI | ChemPort |
   6. Van Hoesen, G. W. Trends Neurosci. 5, 345–350 (1982). | Article |
   7. Kohler, E. et al. Science 297, 846–848 (2002). | Article | PubMed | ISI | ChemPort |
   8. Raos, V., Evangeliou, M. N. & Savaki, H. E. J. Neurosci. 27, 12675–12683 (2007). | Article | PubMed | ChemPort |
   9. Gazzola, V., Aziz-Zadeh, L. & Keysers, C. Curr. Biol. 16, 1824–1829 (2006). | Article | PubMed | ChemPort |
  10. Keyers, C. & Perrett, D. I. Trends Cogn. Sci. 8, 501–507 (2004). | Article | PubMed

Neurobotics

http://www.newyorker.com/online/video/conference/2008/matsuoka

Dislocation of Consciousness

In the Waiting Room by Elizabeth Bishop

In Worcester, Massachusetts,
I went with Aunt Consuelo
to keep her dentist's appointment
and sat and waited for her
in the dentist's waiting room.
It was winter. It got dark
early. The waiting room
was full of grown-up people,
arctics and overcoats,
lamps and magazines.
My aunt was inside
what seemed like a long time
and while I waited and read
the National Geographic 
(I could read) and carefully 
studied the photographs:
the inside of a volcano,
black, and full of ashes;
then it was spilling over
in rivulets of fire.
Osa and Martin Johnson 
dressed in riding breeches,
laced boots, and pith helmets.
A dead man slung on a pole
 "Long Pig," the caption said.
Babies with pointed heads
wound round and round with string;
black, naked women with necks
wound round and round with wire
like the necks of light bulbs.
Their breasts were horrifying.
I read it right straight through.
I was too shy to stop.
And then I looked at the cover:
the yellow margins, the date.
Suddenly, from inside,
came an oh! of pain
--Aunt Consuelo's voice--
not very loud or long.
I wasn't at all surprised;
even then I knew she was 
a foolish, timid woman.
I might have been embarrassed,
but wasn't. What took me
completely by surprise
was that it was me:
my voice, in my mouth.
Without thinking at all
I was my foolish aunt,
I--we--were falling, falling,
our eyes glued to the cover
of the National Geographic,
February, 1918.

I said to myself: three days
and you'll be seven years old.
I was saying it to stop
the sensation of falling off
the round, turning world.
into cold, blue-black space.
But I felt: you are an I,
you are an Elizabeth,
you are one of them.
Why should you be one, too?
I scarcely dared to look
to see what it was I was.
I gave a sidelong glance
--I couldn't look any higher--
at shadowy gray knees,
trousers and skirts and boots
and different pairs of hands
lying under the lamps.
I knew that nothing stranger
had ever happened, that nothing
stranger could ever happen.

Why should I be my aunt,
or me, or anyone?
What similarities 
boots, hands, the family voice
I felt in my throat, or even
the National Geographic
and those awful hanging breasts 
held us all together
or made us all just one?
How I didn't know any
word for it how "unlikely". . .
How had I come to be here,
like them, and overhear
a cry of pain that could have
got loud and worse but hadn't?

The waiting room was bright
and too hot. It was sliding
beneath a big black wave,
another, and another.

Then I was back in it.
The War was on. Outside,
in Worcester, Massachusetts,
were night and slush and cold,
and it was still the fifth 
of February, 1918.

Illusions

Check out this very interesting site: lottolab.org

Itching

http://downloads.newyorker.com/mp3/outloud/080630_outloud_gawande.mp3

Mirror Neurons

pbs.org/wgbh/nova/sciencenow/video/3204/i01.html