Saturday, November 28, 2009
How wonderful that this ailment is currently being highlighted as a condition which could be, potentially at least, reversible with a simple surgical procedure. Who'd have thunk? After all these decades?
Here are the news stories I've come across so far:
CTV W5 The Liberation Treatment
Medpage Radical MS Theory Stirs Interest
BBC: Multiple sclerosis 'blood blockage theory' tested
Edit: I'm back in this post to add a link to Dr. Zamboni's website, Fondazione HILARESCERE.
Some of his papers can be found there. At least for now.
Thursday, November 26, 2009
Part I, and Part II.
In particular, this got my attention;
"There are many interesting details in this account, quite apart from its value as part of the overall argument. Metzinger briefly touches on four varieties of autoscopic (self-seeing) phenomena, all of which can be related to distinct areas of the brain: autoscopic hallucination, where the subject sees an image of themselves; the feeling of a presence, where the subject has the strong sense of someone there without seeing anyone; the particularly disturbing heautoscopy, where the subject sees another self and switches back and forth into and out of it, unsure which is ‘the real me’; and the better-known OBE."
It makes sense to me that multiple self-constructions/constructions of self would exist, given that there are many different body representations all throughout the brain, not just the big S1 map stretched over the top of the cortex, the famous one Wilder Penfield mapped out, and I didn't realize there were names already ascribed to the elicitation of their specific distortions..
A body misperception can be the absence of a familiar body sense just as well as it can be one that's displaced onto a mannequin or onto someone or something else entirely, or floating above.. in each case there will be a corresponding shift in neural traffic flow, the brain not operating in its own familiar manner, and part of it noticing that shift and confabulating predictive perceptual fantasies as to possible reasons why. As in the Charlie Rose Brain Series Part II, in which all the various visual perceptual distortions were touched on, body sense is subject to perceptual distortion. The science on this is younger, but is definitely happening, mostly in Europe, mostly referred to as research of virtual bodies, rubber hand illusions, etc etc. discussedmany times on this blog. It's all very fascinating, and likely to have a lot to do with learning to handle human pain issues much more adeptly with fewer drugs at some point.
Meanwhile, it won't be a bad idea to practice feeling your own normal body better, practice using normal brain pathways, strengthen them so that your brain maps don't get all out of whack some day, and in some misguided attempt at trying to locate body parts, make them spasm or make them hurt to be able to find them more easily - the neurological equivalent of lighting flares to see along a dark path.
1. Book review at Naturalism.org
Sunday, November 8, 2009
I've been away from clinical work for over 4 months now, and my brain is learning to think in different ways. So, when I think of "movement" now, I'm seeing it in more abstract terms. Lately several papers and blogposts about movement have come to my attention. I don't know how they synthesize, yet.. but I'm paying attention to the process, at least. I'd like to outline a few thoughts about them, bearing in mind the role of the brain as predictor, oscillator, simulator. First though, I'm going to just link them here.
1. The Brain in its Body: Motor Control and Sensing in a Biomechanical Context The Hournal of Neuroscience
2. Podcast interview of Barrett Dorko by Rod Henderson, May '09
3. A sensory source for motor variation Nature
4. Physiologically impossible movement of phantom limbs explained at Body in Mind blog (Lorimer Moseley)
5. Tiny Laser-scanning Microscope Images Brain Cells In Freely Moving Animals Science Daily
6. Two Wrongs Make a Right – Abnormal Brain Circuitry May Stop Abnormal Movement BrainBlogger
7. A head of time: For the first time, neuroscientists find brain cells that keep track of time with extreme precision. MIT - Everything gets a timestamp.
8. NOI Notes on Movement as Antigen David Butler's blog/newsletter
9. Primate anterior cingulate cortex: where motor control, drive and cognition interface. 2001
Wednesday, October 21, 2009
This relates to all the posts here to do with robotics, haptics, virtual bodies, virtual body manipulation through mirror therapy or video, and rubber hand illusions. NOI twittered about the Mindhacks post in conjunction with Graded Motor Imagery, the virtual treatment they are promoting. Definitely worth boosting here as well.
Saturday, October 10, 2009
It really makes one wonder what pain is, exactly.
In this story from yesterday (twittered by Mo of Neurophilosophy), a young man's leg was pinned by a concrete girder. He managed to cut most of it off himself, but a friend nearby had to help break the bone.
His brain decided the threat to his ongoing existence was greater than any threat from any upcoming nociception. It was capable of downregulating its own sensory input enough to allow him to remain conscious and focused and on task, as it realized this was its organism's only shot at surviving. In this way the seemingly impossible becomes possible, without loss of consciousness, and in spite of what must be a large loss of blood.
Friday, September 18, 2009
The word "fractal" always conjures up in my mind an image of the Norwegian coastline, then another little tidbit that always has stuck with me, about pi,
"Pi also appears as the average ratio of the actual length and the direct distance between source and mouth in a meandering river (Stølum 1996, Singh 1997)."
From the blogpost:
"The design, results and context for this study are very sophisticated, and the implications are quite abstract. So I’m going to do my best to be clear. First the context: Many natural systems exhibit fractal organization and behavior. A fractal is a branchlike structure. Think of a tree: (1) Trees have many more small branches than large ones. This characteristic is also sometimes called a “power-law” or “inverse power law” or a “1/f” organization. Each of these terms means that there are exponentially more small branches compared to big ones. (2) Trees are “self-similar,” meaning that small branching patterns resemble larger ones. This characteristic is also sometimes called “scale invariance” or “scale free” because no matter the size you are looking at, the general branching shape is the same. (3) The complexity of tree branching patterns can be quantified. Fractals are called “fractals” because they exist in fractional dimensions. A line fits perfectly in one-dimension. A plane (like a piece of paper) fits in two-dimensions. Fractals fit in between a line and a plane (or in the real world between two and three dimensions). More simply, because they are so complex, with huge numbers of tini tiny branches, trees never quite reach three dimensions. If you put them in a box, there will always be some space left over.
You may quickly recognize that many other natural structures besides trees are fractals: Neurons, rivers, the respiratory system, the circulatory system, geological fault lines, snow-flakes, and so on."
As if fractal form doesn't sound complex enough, there is fractal behaviour, apparently:
"Natural systems also produce fractal behavior over time or in dynamics. Earthquakes are a common example. There are many more small earthquakes than large ones (which is nice by the way). Other examples include the size of extinction events in animal species, numbers of academic publications (a few researchers do huge amounts of work and the rest of us do just a little), numbers of hits to web-sites, wait times in stop-and-go traffic, and word usage in literature (i.e., zipf’s law)."
Fractals as verbs as well as nouns. I've often thought of the brain as more verb than noun.
Thursday, September 10, 2009
This paper came to my attention yesterday: The kinesthetic senses by Uwe Proske and Simon Gandevia, in Australia. By some refreshing turn of events, it is open access. It provides an historical backdrop to nearly everything we as physical therapists are about. We are all about restoring this function, kinesthesia, to people in whom it would seem to have gone missing. We always have been. Without good kinesthesia, motor control goes offline. When motor control goes off line, so does maximal function.
The paper begins with a brief intro to kinesthesia. It states at the outset that muscle and skin receptors account for most of the receptor input that helps the brain make motor choices. It specifically states,
"Peripheral receptors which contribute to kinaesthesia are muscle spindles and skin stretch receptors. Joint receptors do not appear to play a major role at most joints."
Wow. Right there, we can see a huge erosion under the sea shore of one of the defining organizational principles of orthopaedic manual therapy, which is that getting to and wiggling or popping the right joint in the right way will jumpstart a better motor output. Orthopaedic manaual therapy (and chiro) have used this idea to build themselves and have perpetuated it for decades, for a century. It's just not valid. It was a false hypothesis, and finally research has begun to trickle out that suggests this is the case.
After a brief description of the contribution of muscle spindle receptors to the kinesthetic senses, Proske and Gandevia begin to discuss receptors found in skin:
"Concerning the possible contribution to kinaesthesia from other receptor types, the summary view is that while a good case has been made for some cutaneous receptors, the evidence is less convincing for joint receptors. The cutaneous receptor most likely to subserve a kinaesthetic role is the skin stretch receptor, the slowly adapting Type II receptor served by Ruffini endings (Chambers et al. 1972; Edin, 1992). For kinaesthesia at the forearm, stretch of skin over the elbow during elbow flexion can provide information about both position and movement. Movement illusions generated by stretch of skin of the hand and over more proximal joints, when combined with muscle vibration were greater than when either stimulus was applied on its own (Collins et al. 2005). The authors made the point that this was not just a matter of skin input facilitating the muscle input and that cutaneous input generated by skin stretch contributed to kinaesthesia in its own right. More recent observations have shown that skin input can also have an occluding action. Signals from local, rapidly adapting receptors evoked by low-amplitude, high frequency vibration can impede movement detection (Weerakkody et al. 2007).(....)
While joint receptors were first thought to be all-important in kinaesthesia, the present-day view is that their contribution at most joints is likely to be minor. Typically they respond to joint movement, but often with response peaks at both limits of the range of joint motion (Burgess & Clark, 1969). They are now thought of as limit detectors. However, there are examples in the literature of responses across the full range of joint movement (Burke et al. 1988) and here joint receptors may play a role under circumstances in which input from muscle and skin is not available (Ferrell et al. 1987). "
This paper is an important one for manual therapists who seek to understand how it is that "light" manual techniques seem to do as well to help patients' brains connect up in terms of improved, observable motor output, as heavy joint-based, manipulative or mobilizing ones.
Proske, U., & Gandevia, S. (2009). The kinaesthetic senses The Journal of Physiology, 587 (17), 4139-4146 DOI: 10.1113/jphysiol.2009.175372
Friday, August 14, 2009
Wednesday, August 12, 2009
A New Integrative Theory for Cortical Pyramidal Neurons.
Thank you for this, AK.
Tuesday, August 11, 2009
He says confounding factors include neuroplasticity, ignoring the functions of neuroglia, and ordinary small-scale variations that occur:
"the connectome apparently ignores the phenomenon of neuroplasticity.
Plasticity refers to the brain’s ability to physically alter its structure in response to experience. Far from being immalleable, as was once thought, the brain is a highly dynamic organ. Neurons can sprout new connections within minutes of a given stimulus, and entire neural pathways can be rerouted so that function is recovered after a brain injury.
The connectome also disregards the functional importance of neuroglial cells, another class of cells which are found in the nervous system and which outnumber neurons by at least 10 to 1. Once thought to merely provide structural and nutritional support for neurons, glia have, in recent years, come into their own as key players in the brain. As well as performing the roles initially ascribed to them, glia carry out a whole host of other vital functions, including monitoring neuronal health, identifying damaged neurons, and regulating synaptic plasticity. They are also known to be capable of communicating not only with one another, but also with neurons. A map of brain connectivity cannot therefore be complete without taking glia into account.
Finally, although the large-scale connections are very similar among individuals, there are significant variations at smaller scales."
Sunday, August 2, 2009
Last night I read "Microbes exploit groundhog day" in Nature's July issue. Excerpt:
"The proposal that microorganisms can associate a stimulus with an appropriate response to a future environment might seem far-fetched. After all, without cognition, microorganisms rely on simple regulatory networks to sense and respond to their environment. A canonical example of gene-regulation, the response of Escherichia coli to the sugar lactose, illustrates why it seems surprising that such networks can be used to anticipate environmental changes."The write-up discusses a paper by Mitchell et al., Adaptive prediction of environmental changes by microorganisms (same issue).
"The insight of Mitchell et al., building on previous work, was to realize that the connection between stimulus and response can be offset in time. For example, if a non-lactose sugar consistently follows the availability of lactose, selection might favour the evolution of a regulatory network that directly links the presence of lactose to the expression of the non-lactose-utilization genes. This network would serve to 'prime' cells conferring an advantage by preparing them to use the non-lactose sugar in anticipation of its imminent availability and thereby reducing the lag time characteristic of de novo activation of response genes. Mitchell et al. call this mechanism adaptive anticipatory conditioning."A clever experimental design was employed to examine the responses of E. coli and baker's yeast, Saccharomyces cerevisiae, to an environment simulating what each organism would ordinarily find in a typical higher intestinal tract (higher in lactose and low in maltose), compared to lower part of the tract (low in lactose and higher in maltose). Mitchell et al. found that "microorganisms can interpret their environment and respond in a way that provides a benefit only in following a future environmental change." A few wrinkles remain, but "one message is clear" -
"The regulatory networks that link environmental stimuli to microbial responses are complex and can evolve rapidly. The potential for microorganisms to offset responses from environments in which those responses are useful provides both a warning and an opportunity for researchers involved in testing the functional significance of links between stimuli and responses."Possibly related, in some way, somewhere down the road, are these two recent tidbits from New Scientist:
1. Memristor minds: The future of artificial intelligence by Justin Mullins. It discusses artificial intelligence and a "fourth" ingredient, "memristor" (in addition to resistor, capacitor and inductor):
"Chua had anticipated the idea that memristors might have something to say about how biological organisms learn. While completing his first paper on memristors, he became fascinated by synapses - the gaps between nerve cells in higher organisms across which nerve impulses must pass. In particular, he noticed their complex electrical response to the ebb and flow of potassium and sodium ions across the membranes of each cell, which allow the synapses to alter their response according to the frequency and strength of signals. It looked maddeningly similar to the response a memristor would produce. "I realised then that synapses were memristors," he says. "The ion channel was the missing circuit element I was looking for, and it already existed in nature."
To Chua, this all points to a home truth. Despite years of effort, attempts to build an electronic intelligence that can mimic the awesome power of a brain have seen little success. And that might be simply because we were lacking the crucial electronic components - memristors." - (my bold)
2. Evolution's third replicator: Genes, memes, and now what? by Susan Blackmore. She comments (excerpts):
"We humans have let loose something extraordinary on our planet - a third replicator - the consequences of which are unpredictable and possibly dangerous.
What do I mean by "third replicator"? The first replicator was the gene - the basis of biological evolution. The second was memes - the basis of cultural evolution. I believe that what we are now seeing, in a vast technological explosion, is the birth of a third evolutionary process. We are Earth's Pandoran species, yet we are blissfully oblivious to what we have let out of the box."
"Billions of years ago, free-living bacteria are thought to have become incorporated into living cells as energy-providing mitochondria. Both sides benefited from the deal. Perhaps the same is happening to us now. The growing web of machines we let loose needs us to run the power stations, build the factories that make the computers, and repair things when they go wrong - and will do for some time yet. In return we get entertainment, tedious tasks done for us, facts at the click of a mouse and as much communication as we can ask for. It's a deal we are not likely to turn down."Additional resources:
1. BrainScience Podcast #51 Dr. Seth Grant on Synapse Evolution
Thursday, July 2, 2009
This is an excellent overview on brain development and neural plasticity.
Merzenich is a pioneer in research on the topic and in finding practical ways to work with it, e.g., his development of cochlear implants.
1. Michael Merzenich's blog, On the Brain
2. BrainSciencePodcast #54 with Dr. Ginger Campbell, Interview with Michael Merzenich on Neuroplasticity
Friday, May 22, 2009
On page 17 he has listed these four ways neuroplasticity operates:
"1. By (functional) changes in synaptic efficacy, the extreme of which is unmasking of dormant synapses, or masking of efficient synapses.
2. By reducing or modifying protein synthesis and proteinase activity in nerve cells.
3. By creation of new anatomical connections (sprouting of axons and dendrites) or elimination of existing connections or by altering synapses morphologically.
4. By elimination of nerve cells (apoptosis)."
1. A quick search of blogposts re: neuroplasticity on Deric Bownd's Mindblog
2. A quick search of blogposts re: neuroplasticity on Mo's Neurophilosophy blog (and some others).
3. A quick search for neuroplasticity on this blog, Neurotonics.
4. A related blogpost, System Proteomics
Tuesday, May 19, 2009
You can take a look at brain parts, look into different levels of the brain, turn it all around, flip it upside down or look into it through the top.
You can click on and explore different conditions, or different functions.
I found the G2C site at the brain portion of the Dana Foundation website. I found the brain portion of the Dana Foundation website by clicking on the main page. I found the main page by clicking on the link provided by Deric Bownds in his new post, Arts and the Brain. Thank you Deric!
Sunday, May 17, 2009
Lately he's been studying a patient, dubbed for the article, "Arthur Jamison". I am going to provide excerpts from the article now, direct quotes:
"Jamieson is seventy years old and lives in the Midwest. He is a physician and an amateur cellist, and has been married for forty-seven years. He also suffers from a rare and bewildering condition called apotemnophilia, the compulsion to have a perfectly healthy limb amputated--in his case, the right leg, at mid-thigh."
"After interviewing several apotemnophiliacs--Jamieson is the ﬁfth person with the disorder whom he has studied--Ramachandran was struck by the fact that all of them said they became aware of the compulsion in early childhood, that it centered on a particular limb (or limbs), that they could draw a line at the exact spot where they wanted the amputation to occur, and that they attached little or no erotic signiﬁcance to the condition. Furthermore, none rejected the limb as "not belonging" to them, as some stroke victims do in the case of a paralyzed arm or leg, and as Ramachandran had predicted they might. Instead, they said that the limb over-belonged to them: it felt intrusive. "If you talk to independent apotemnophiliacs, they say the same bloody things," Ramachandran told me. " 'The line for cutting is here.' 'It started in early childhood.' 'It's over-present.'
They're not crazy.""
"Asked where he would make the cut line for the amputation, Jamieson unhesitatingly drew an index ﬁnger across the middle of his right thigh. As to whether he felt that his leg didn't "belong" to him, Jamieson was emphatic. "Somehow, for me, that just doesn't compute, that kind of language," he said. "I have always been fascinated by amputation and wished that I had one. Why? Who the hell knows?"
"Ramachandran and other researchers have shown that the brain is what scientists call "plastic"--it can reorganize itself. Not only are different regions of the brain engaged inongoing communication with one another, with the body, and with the surrounding world; these relationships can be manipulated in ways that can reverse damage or dysfunction previously believed to be permanent. Ramachandran's work with patients at U.C.S.D. has led to one of the most effective treatments for chronic phantom-limb pain and to a new therapy for paralysis resulting from a stroke. (In both instances, his treatment involves only a ﬁve-dollar household mirror.) It has also provided suggestive insights into the physiological cause of such mystifying syndromes as autism."
"In the seventies, Michael Merzenich became expert at using microelectrodes to map the sensory cortex of monkeys. In one experiment, he mapped a monkey's hand area in the brain, then amputated its middle ﬁnger. Some months later, he remapped the monkey's hand and discovered that the brain map for the missing ﬁnger had vanished and been replaced by maps for the two adjacent ﬁngers, which had spread to ﬁll the gap. The results, published in the Journal of Comparative Neurology in 1984, were decisive proof that the brain can reorganize itself--at least across very short distances of one to two millimetres."
"After interviewing Jamieson in his ofﬁce, Ramachandran led him to a lab for a Galvanic Skin Response, or GSR, test, which would reveal how Jamieson's legs reacted to a mild pain stimulus... David Brang, one of Ramachandran's graduate students, attached a sensor to the middle two ﬁngers of Jamieson's right hand using a Velcro strap. The sensor would measure the reaction of Jamieson's sympathetic nervous system by monitoring the sweat on his ﬁngers. With a sterilized pin, Brang pricked Jamieson's legs at random points, waiting a few seconds between each prick. A scrolling graph on the computer screen registered Jamieson's responses.
The unaffected leg--the left one--and the right leg above where he wished to have it amputated showed a normal response: the graph at ﬁrst shot upward with each prick, but with further pricks it ceased to rise, then began to ﬂatten out, indicating that Jamieson's nervous system was getting used to the stimulus. But when Brang pricked Jamieson anywhere on the leg below the amputation line, his nervous system responded with increasing distress, the graph climbing higher and higher with each prick.
The experiment seemed to support Ramachandran's theory about the disorder. He believed that people with apotemnophilia had a deﬁcit in the right superior parietal lobule, where the body-image map is assembled. According to this notion, Jamieson was missing the neurons in the map that corresponded to his right leg from the mid-thigh down. He had normal sensation in the unwanted part of his leg--he felt the pin prick. But when the pain signal travelled to the right superior parietal lobule there was nothing in the body-image map to receive it.
"So there's a big discrepancy--a clash--and the brain doesn't like discrepancies," Ramachandran said."When a discrepancy comes in, it says, 'Shit! What the hell is going on here?,' and it kicks in and sends a message to the insular part of the brain, which is involved in emotional reactions--so you're getting this crazy GSR." In apotemnophilia sufferers, the discrepancy causes a feeling of distress that is no less agonizing for being below the level of conscious awareness.
In the past two years, Ramachandran has tested four other apotemnophiliacs using MEG brain scans. "You touch them anywhere in the body and the right superior parietal lobule lights up, as you would expect," Ramachandran said. "But if you touch him here"--he gestured to a point on Jamieson's leg below the amputation line--"nothing happens." Ramachandran said that the experiment needed to be repeated by other researchers, but, he added, "This takes a spooky psychological phenomenon and, as Shakespeare said, gives it a 'habitation and a name.' " Furthermore, the ﬁndings suggested to Ramachandran a possible method for alleviating the oppressive sensations in the unwanted limb.
Later, he asked Jamieson to stand in a corner of his ofﬁce and placed a three foot-high mirror in front of him, in such a way that in place of his right leg Jamieson saw his left, which he held bent at the knee. Jamieson gazed into the mirror. "Astonishing," he said. For a moment, the leg looked "right.""
This is fascinating stuff. I was reminded of reading Michael Gershon's book The Second Brain, about the gut and enteric nervous system, how if neural crest cells didn't make it in to colonize the large intestine, Hirschsprung's Disease (Megacolon) is the unfortunate result. So much depends on exquisite timing during embryological unfoldment. Miss one little beat and some batch of baby neurons won't exist, and the resulting human organism can end up with major deficit. It can affect the body, and maybe, as in the case of Apotemnophilia, one's sensory perception of one's body.
As I checked out Apotemnophilia online, I saw it was quite consistently coupled with notions of a sexualized nature with heavy overtones of psychiatric implications.
About this, Colapinto writes:
"Jamieson, who was born and raised in New York City, ﬁrst remembers having an unusual relationship with his right leg when, at around the age of seven, he was waiting for a bus. He found himself thinking that if he stuck out his leg it would be crushed and severed by the bus. "What came to me was not 'No, I don't want to do that' but 'How would I ever explain this?' " he told Ramachandran. In recounting his childhood memories, he said, "One of the things that's astonishing to me is how clear these recollections are."
"These things are very salient," Ramachandran said... "It's interesting to contrast these very clear-cut descriptions with these vague, Freudian notions about this whole phenomenon--that it's primarily connected with sexual stuff."
"Yeah," Jamieson said with disgust. "I've got no desire to cozy up to anyone with a stump. It's psychobabble.""
That it could be due to some embryologic formation error makes more sense. The thigh is actually the last part of the leg to form. Feet (in the form of ectodermic limb buds) poke out first, from the body wall. As toes begin to form, these feet, already containing vasculature and neural structure, begin to lengthen away from the body wall, and the "lines" of supply (vasculature) and communication (nerves) must grow to keep pace. Within the lengthening limb buds, bones begin to condense from cartilaginous masses which have formed from prior condensations of mesoderm; neural and vascular structures must simultaneously penetrate these condensations. Pathways of sensation of a limb to a brain include not just large diameter fibers from skin, but also many sorts of receptors, some very tiny, which report on all sorts of tissue, including vascular tissue (nervi vasorum). Some of these report on the sensory nerves themselves (nervi nervorum). Lots end up just inside the spinal cord, while others get all the way up as far as the insular cortex (1). The brain uses information coming in from many parallel kinesthetic channels(3) as well as visual ones, to construct its sense of self and body awareness/embodiment, to learn who is touching its organism, how it feels about that, what salience to assign in that moment. Apparently some sort of reverse processing occurs between afferents that go to the somatosensory cortex and those that go only to the insula(2). Apparently those going to the left insula are processed differently from those which go to the right (4).
All it would take would be some little screw-up in neural crest implantation into either the limb itself or else at the other end, in the brain itself (it would seem that quite a bit of "peripheral" "nerve", from neural crest, goes all the way into the brain, into some of its very touchy touch processing areas), so I can see how neural crest mishaps could be connected with body perception problems. Perhaps neural crest abnormality might become a target of investigation for body perception disorders some day.
1. Unmyelinated tactile afferents signal touch and project to insular cortex (Olausson et al.)
2. Unmyelinated tactile afferents have opposite effects on insular and somatosensory cortical processing. (Olausson et al.)
3. Unmyelinated afferents constitute a second system coding tactile stimuli of the human hairy skin. (Olausson et al.)
4. Coding of pleasant touch by unmyelinated afferents in humans. (Löken et al.)
Here is an excerpt I thought was particularly interesting:
"Now, one of the characteristics of this change process is that information is always related to other inputs or other information that's occurring in immediate time, in context. And that's because the brain is constructing representations of things that are correlated in little moments of time, and that relate to one another in little moments of successive time. The brain is recording all information and driving all change in temporal context.
Now, overwhelmingly, the most powerful context that occurred in your brain, is "you". Billions of events occurred in history that are related in time to your "self" as the receiver, your "self" as the actor, your "self" as the thinker, your "self" as the mover.
Billions of times, little pieces of sensation have come in from the surface of your body, that are always associated with "you," the receiver, and result in the embodiment of "you". "You" are constructed. Your "self" is constructed from these billions of events; it's constructed, it's created in your brain and it's created in the brain by physical change. This is the marvelously constructed thing that results in individual form, because each one of us has vastly different histories, and vastly different experiences, that drive into us this marvelous differentiation of self, of personhood."
I love this video. It makes me glad I picked the sort of work I did. I quite like the idea that when I put my hands on someone else, I'm helping them learn more about who they are, helping that brain add to its construction of "self" outside of a pain construction (if I'm careful, and I am). I like that I'm adding more "little pieces of sensation" to their temporally correlated process of embodied self, minus nociceptive input, i.e., more "danger" signals. Yeah, I can live with that.
I also like the idea that I learn more about/add to my own self-construct at the same time, as "little pieces of sensation" from my own skin (on my hands) enters my brain and is temporally correlated to what is already in there.
What is already in there? Circuitry routes, billions of neurons, receptor sites on them (lots and lots of receptors that can change to different ones, alter what they are sensitive to, thanks to "synaptic plasticity") and transmitters. There are convergence zones and arborizations, ascending and descending fibers, switchback and feed forward stations, and lots of somatotopic representational areas (brain maps of body parts). There is brain behaviour, and parts or areas that light up for pain as well as for other functions on fMRI, a vastly complex ecosystem, embedded within another outer ecosystem called the "body," with which it is completely integrated, both of which must exist co-mingled and learn to help each other within the greater outer planetary ecosystem, via a construct called "self."
1. Michael Merzenich's TED bio
2. A page from my website, About Pain
Older blogposts on Neuroplasticity
1. Neuroplasticity (Dec 11, 2007)
2. Learning (Dec 12, 2007)
3. History of Neuroplasticity (Dec 12/2007)
4. Paradigm (Dec 16, 2007)
5. About mirror therapy (Dec 16, 2007)
6. Get your game on, ease your pain (Dec 17, 2007)
7. The devil is in the details (Dec 18, 2007)
8. A few types of Learning (Dec 18, 2007)
9. Cart ruts: More about UN-doing something (Dec 29, 2007)
10. And it's about brain parts: like hippocampus (Dec 30, 2007)
11. Function only (January 15 2008)
12. Smart prosthetics, smart nerves, smart brains (February 10, 2008)
13. Nervous System Basics VIII: PLASTICITY (May 10, 2008)
14. More about neurogenesis (June 7, 2008)
15. "Dialogues in Clinical Neuroscience" online (August 23, 2008)
Monday, May 11, 2009
"Antonio and Hanna Damasio and collaborators have now observed brain activities associated with our internal loftier emotions that transcend self-interest, such as elevation and admiration. These are hard to measure because they don't correlate obviously with facial expressions or body language."
Writers at PNAS (again, from Deric's blogpost) provide an overview, put the paper into context:
"Emotion research has something in common with a drunk searching for his car keys under a street lamp. ‘‘Where did you lose them?’’ asks the cop. ‘‘In the alley,’’ says the drunk, ‘‘but the light is so much better over here.’’ For emotion research, the light shines most brightly on the face, whose movements can be coded, compared across cultures, and quantified by electromyography. All of the ‘‘basic’’ emotions described by Paul Ekman and others (happiness, sadness, anger, fear, surprise, and disgust) earned their place on the list by being face-valid. The second source of illumination has long been animal research. Emotions that can be reliably triggered in rats, such as fear and anger, have been well-studied, down to specific pathways through the amygdala. But emotions that cannot be found on the face or in a rat, such as moral elevation and admiration, are largely abandoned back in the alley. We know they are there, but nobody can seem to find a flashlight. It is therefore quite an achievement that Immordino-Yang, McCall, Damasio, and Damasio managed to drag an fMRI scanner back there and have given us a first glimpse of the neurological underpinnings of elevation and admiration."
Here is the abstract of the paper itself;
In an fMRI experiment, participants were exposed to narratives based on true stories designed to evoke admiration and compassion in 4 distinct categories: admiration for virtue (AV), admiration for skill (AS), compassion for social/psychological pain (CSP), and compassion for physical pain (CPP). The goal was to test hypotheses about recruitment of homeostatic, somatosensory, and consciousness-related neural systems during the processing of pain-related (compassion) and non-pain-related (admiration) social emotions along 2 dimensions: emotions about other peoples' social/psychological conditions (AV, CSP) and emotions about others' physical conditions (AS, CPP). Consistent with theoretical accounts, the experience of all 4 emotions engaged brain regions involved in interoceptive representation and homeostatic regulation, including anterior insula, anterior cingulate, hypothalamus, and mesencephalon. However, the study also revealed a previously undescribed pattern within the posteromedial cortices (the ensemble of precuneus, posterior cingulate cortex, and retrosplenial region), an intriguing territory currently known for its involvement in the default mode of brain operation and in self-related/consciousness processes: emotions pertaining to social/psychological and physical situations engaged different networks aligned, respectively, with interoceptive and exteroceptive neural systems. Finally, within the anterior insula, activity correlated with AV and CSP peaked later and was more sustained than that associated with CPP. Our findings contribute insights on the functions of the posteromedial cortices and on the recruitment of the anterior insula in social emotions concerned with physical versus psychological pain.
I deliberately bolded the bit about the anterior insula, because of how involved it seems to be in pain production or at least pain perception.
Sunday, April 19, 2009
1. Scott Mackler
2. Smart Prosthetics, Smart Nerves, Smart Brains
3. More Smartness
4. Monkey Robotics
5. Monkey intentions and control of a robot arm
Thursday, March 12, 2009
Saturday, February 7, 2009
She can say that again. Not only does the scanning or imaging process do nothing whatever for the "pain", it may result in misleading interpretations of the imaging; well-meaning people may consider or resort to treatments that reinforce the problem rather than help the pain experience to disappear.
"Researchers from Oregon Health and Science University in Portland reviewed six clinical trials comprised of nearly 2,000 patients with lower back pain. They found that back pain patients who underwent scans didn’t get better any faster or have less pain, depression or anxiety than patients who weren’t scanned. More important, the data suggested that patients who get scanned for back pain may end up with more pain than those who are left alone, according to the report published this week in the medical journal Lancet."
"The problem, say researchers, is that back scans can turn up physical changes in the back that aren’t really causing any problem."
“You can find lots of stuff on X-rays and M.R.I.’s like degenerative disks and arthritis, but these things are very weakly correlated with low back pain,” said study author Dr. Roger Chou, associate professor of medicine at Oregon Health. “We think we’re helping patients by doing a test, but we’re adding cost, exposing people to radiation and people may be getting unnecessary surgery. They start to think of themselves as having a horrible back problem and they stop doing exercise and things that are good for them, when in reality, a lot of people have degenerative disks and arthritis and have no pain at all.”
I completely agree. In addition to unnecessary surgery, they may be getting unnecessary manipulation and other "treatment" which is focused on supposedly misbehaving mesodermal derivatives instead of helping the ectodermal derivatives (i.e., skin, nerves, brain, embedded "I"- illusion) all learn to get along better.
Monday, January 12, 2009
"What's a neuroprosthesis? It's a device made up of sensors, connections and electronic chips that are embedded in the body to repair certain neurological deficiencies. Recent progress in artificial retinas and man-machine interfaces that permit communication or action via thoughts alone gives us a glimpse of the possibilities the future might hold for improving the lives of the handicapped. The new Center will concentrate on six main themes: vision (retinal implants), hearing (cochlear implants), mobility (cortical and spinal implants), non-invasive man-machine interfaces (piloting at distance, robotics), the micro-and nano-fabrication of implants, and neuronal coding (signal processing, sensors).Other posts on how prolific neuroresearch appears to be in Switzerland:
The Center will be inaugurated on January 1, 2009, and will formally be part of EPFL's School of Engineering, in collaboration with the School of Life Sciences and the School of Computer and Communication Sciences. This project also opens the door to fruitful collaborations with other institutions in the Lake Geneva area, such as University of Lausanne and the Cantonal Hospital (CHUV)), University of Geneva and its hospital (HUG), and the regional biomedical industry."
1. Virtual Body Experience
2. Something in Swiss water?
3. More from Lausanne: Mapping the structural core of the human cerebral cortex
4. Smelling someone else's alarm bells
On a related topic, related in terms of collaborative projects done by teams of people, in this case by a private backer, reader Kent sent me a link to Piece of Mind, from the Economist.
"When we first put the mouse-brain atlas online free, it was met by the research world with suspicion. People wondered what the catch was. Scientific research has long been a solitary endeavour—one researcher, one microscope. Findings are protected so that discovery credit can be clearly defined and awarded. This is a successful model and will continue to be.Nothing but good will come out of this, I'm sure. Seth Grant, who recently decoded human synapse proteomics, used free genomic data bases to arrive at new perspectives on how evolution of the nervous system has proceeded. (Here is a blog post about that.) Listen to Ginger Campbell's BrainSciencePodcast #51 interview with Dr. Grant. (It was my pleasure to transcribe the interview - the transcription is linked to the podcast shownotes.)
However, the Human Genome Project demonstrated a different path: multiple teams working collaboratively towards a common goal (...) We wanted the mouse atlas to be free and available for all to use as the basis for foundational research and discovery.A new generation of implantable pacemakers for the brain will be widely used to treat everything from depression to addiction and Parkinson’s disease
If we thought it would be a hit right out of the gate, we were slightly wrong. It took a while for people to trust that it really was free to use. No one believed in a free lunch.
Now, things have changed. Today we have many scientists using the atlas for their research into Alzheimer’s, bipolar disorders, Down’s syndrome, Parkinson’s, fragile x mental retardation and epilepsy. The atlas is also giving scientists insight into alcoholism, obesity, sleep, hearing and memory.
The greatest testament to what we did was that researchers of spinal-cord diseases, trauma and disorders approached the institute and asked us to create a spinal-cord atlas, which is now close to completion. We will launch the first phase of a human-brain atlas, a four-year project, in 2010.
Like the Human Genome Project, the Allen Brain Atlases and Spinal-Cord Atlas have helped democratise the scientific landscape. When you can log on to a map of gene expression from anywhere in the world, more people can enter the scientific conversation. The result is a massive saving in time, since without the atlas each researcher could spend a lifetime trying to gather complete gene-expression data for his or her work."