Wednesday, January 30, 2013

Mechanical deformation of a peripheral neural structure

Here is a slide I made based on an image in an old, out-of-print but nevertheless extremely valuable Lundborg book, Nerve Injury and Repair. I see there is an online version

Anyway, this slide depicts what happens to the intraneural microcirculation system during mechanical deformation. Imagine the area labelled "ligature" not as a ligature, but rather as a grommet hole in fascia. Then imagine the neural structure being pulled away from the grommet hole, to which it is circumferentially attached, either:

1. into the body, by some unconscious muscular force generated in the spinal cord perhaps, way below conscious awareness, pulling it sideways, because it's trying to alleviate the irritation arising in some other part of the 72 kilometer long fuzzball known as the peripheral nervous system, and unintentionally saws away, instead, on this new piece of the fuzzball, and on its microcirculation; or..


2. outside the body, by some kind of unrelieved static skin layer contact/fixation against/with the external world, e.g., bottoms of feet on concrete or butt against chair seat, or elbow on arm rest or hand on mouse, while the rest of the body moves inside itself. 






It doesn't matter at first - there is so much redundancy - but eventually our bad lack-of-movement habits catch up and pain starts up seemingly out of nowhere. 


If we take our pain in to see a biomechanist, he or she will diagnose all sorts of postural and positional faults, then try to "cure" them. Such is the clunky conceptual lens of the biomechanist operator who relies on playing with bones for constructing his or her perceptual fantasies of "normal" movement. 


If we take our pain in to see a dermoneuromodulator or anyone with a clue about what the NS consists of or how it works out in the body or what it needs, they might be able to coax the system into feeding itself again; in fairly short order the motor output will change into something less static and more dynamic, and the pain "problems" will solve themselves, because they were never "nouns" in the first place - they were just verbs that stopped being able to move, physiologically.

Wednesday, January 23, 2013

Helping the "self"


The Self in Self-Help, by Kathryn Schultz, Jan 6, NewYork Magazine

I just read this, today, and very much like how it fits into/ contrasts with the Master and his Emissary posts, and how it compares to how I have helped my "I" illusion through depression all my life, by taking ownership, responsibility, and changing context as frequently as required, even though another part of me hates being having to be uprooted. 

Excerpt:
"The journalist Josh Rothman once wrote a lovely description of what a cloud really is: not an entity, as we perceive it, but just a region of space that’s cooler than the regions around it, so that water vapor entering it condenses from the cold, then evaporates again as it drifts back out. A cloud is no more a thing, Rothman concluded, than “the pool of light a flashlight makes as you shine it around a dark room.” And the self, the Buddhists would say, is no more a thing than a region of air with thoughts passing through."

Excerpt: 

"I have no idea how I got over my depression. I spent a year doing the things one does: I read Feeling Good, went to therapy, got exercise, tried to eat well in the utter absence of appetite, and routinely forced myself into sympathetic company when every particle of my being—or, I suppose, every particle but one—wanted to curl up alone in the dark. I did all these things not out of any real hope that they would work but because the failure to do them seemed like it would cede more ground to the awfulness. And then some moon in my inner universe set silently, and the awfulness went out like a tide...  








"...In other words, as scientists would say, this method of self-help is an uncontrolled experiment. But so what? Life is an uncontrolled experiment: confounded, confounding, and, above all, completely impossible to replicate—tragically so, and wonderfully so. I try to remind myself of that as often as I can. Sometimes it helps."





Sunday, January 20, 2013

Seeing and responding to the big picture


The Master and His Emissary



Previously in this series:


The malleableness of things   Dec18/12  
Two brain halves, disappearing bridge Dec 21/12  
Mind: the brain's experience of itself Dec 22/12  
Asymmetry of brain sides: size, structure, neurochemistry Dec 31/12
Those great big lobes Jan 4/13

RIGHT HEMISPHERE HAS BROAD SCOPE

From page 40-41:
If we try to rely only on left-hemisphere attention on its own, i.e., if the right hemisphere is knocked out somehow, we end up with:
1. inability to adjust the "spotlight"of attention
2. permanent narrowing of the attentional window
3. the need to start with pieces to build up a picture, rather than being able to see the entire picture in one go.

Like looking out at life through a crack in the wall instead of being able to stick one's head clear out the window.

NOVELTY, ENVIRONMENT AND CONTEXT
McGilchrist:
".. in almost every case what is new must first be present in the right hemisphere, before it can come into focus for the left. For one thing, the right hemisphere alone attends to the peripheral field of vision from which new experience tends to come; only the right hemisphere can direct attention to what comes to us from the edges of our awareness, regardless of side."
"Anything newly entering our experiential world instantly triggers a release of noradrenaline - mainly in the right hemisphere." 
(my bold)
"Novel experience induces changes in the right hippocampus, but not the left."
In other words, "phenomenologically it is the right hemisphere that is attuned to the apprehension of anything new." Novel stimuli. Contact with a patient's body. Threat detection. Salience conferring. Critter brain.

He goes on:
" Not just new experience, but the learning of new information or new skills also engages right-hemispheric attention more than left, even if the information is verbal in nature." 
Once learned through practice, the left hemisphere takes them over, "even for skills such as playing a musical instrument."

The right hemisphere is the novelty seeker. Scans for discrepancy. Looks for, brings in new information.
"The left hemisphere deals with what it knows, and therefore prioritizes the expected - its process is predictive. It positively prefers what it knows." 
(My bold)

The left hemisphere is a good manager when everything is going along as usual, but it's useless in a crisis. Because it relies on its own expectations.
"The right hemisphere outperforms the left whenever prediction is difficult." 
Even horses prefer to size up a new element in their immediate environment (potential threat, "possibly emotionally arousing stimuli") with their left eye/right hemisphere. 
"The right hemisphere is... more capable of a frame shift".. especially important for flexibility of thought." 
Damage to it leads to perseveration, pathological inability to respond flexibly to changing situations, incapacity to figure out a new way to deal with a novel situation.
"It is the right frontal cortex that is responsible for inhibiting one's immediate response, and hence for flexibility and set-shifting, as well as the power of inhibiting immediate response to environmental stimuli." 
PROBLEM-SOLVING
"..the right hemisphere presents an array of possible solutions, which remain live while alternatives are being explored. The left.. takes the single solution that seems best to fit what it already knows and latches on to it." 
The left jumps to conclusions. Inappropriately. The right hemisphere sounds more thoughtful, more exploratory, more comfortable with uncertainty and possibility, more "scientific".

The left has the "tendency to deny discrepancies that do not fit its already generated schema of things. The right.. by contrast, is actively watching for discrepancies, more like a devil's advocate. These approaches are both needed but pull in opposite directions."

LANGUAGE SKILL
Both hemispheres participate:
"..the left hemisphere actively narrows its attentional focus to highly related words while the right activates a broader range of words."  
" The left hemisphere operates focally, suppressing meanings that are not currently relevant. By contrast, the right hemisphere 'processes information in a non-focal manner with widespread activation of related meanings'"  
" ..close lexical semantic relationships rely more on the left hemisphere, looser semantic relationships rely on the right."
The right hemisphere "makes infrequent or distantly related word meanings available", is involved in "generating unusual or distantly related words or novel uses for objects."
The right anterior temporal region is involved in "making connections across distantly related information during comprehension." The right posterior superior temporal sulcus might have something to do with verbal creativity. 
"In the 'close' situation..the left hemisphere actively suppresses the right, to exclude associations which are semantically only distantly related."
The right hemisphere can use the left hemisphere's preferred style, but the left cannot use the right's. Huh. Who'da thunk it. 
"..although the left hemisphere gains more benefit from a single strong association than several weaker associations, only the right hemisphere can use either equally." 
Wow. 
I must admit, I am enjoying these revelations. 

REFERENCES:
1. Larose CRichard-Yris MAHausberger MRogers LJLaterality of horses associated with emotionality in novel situationsLaterality. 2006 Jul;11(4):355-67.













Saturday, January 19, 2013

Safe spaces for demented people

I'm absolutely charmed: In the Netherlands, an experiment is underway - an enclosed care facility designed to feel and look and operate like "real life", where dementia patients can roam around freely, buy groceries, get a haircut, attend events, and remain supervised and safe. Read ‘Alternative Reality’ Villages for Dementia Sufferers, by Marianne Cezza, at Nodes of Ranvier blog. She tweets as  .

Here is a short video, Dementia patients in Dutch village given 'alternative reality'.



This makes me ache, because it is so touching. Such a simple no-brainer right thing to do. 

Well, not easy I imagine, or cheap. But what a huge boon for people who can no longer cope 
with "real" existence, because they have become too confused and vulnerable. 
What a kind way to ease the burden of the big human brain in which so many things can go wrong
in the data storage department, but which still has a critter brain which can feel stressed and miserable
under so many kinds of circumstances, including "hard drive" degradation.  

Friday, January 04, 2013

Those great big lobes

The Master and His Emissary


Other posts in this series:

The malleableness of things   Dec18/12  
Two brain halves, disappearing bridge Dec 21/12  
Mind: the brain's experience of itself Dec 22/12  
Asymmetry of brain sides: size, structure, neurochemistry Dec 31/12



"Every individual mind is a process of interaction with whatever it is that exists apart from ourselves according to its own private history." - p.20.

How can you tell I'm practically paralyzed by this book? Here I am, catching myself back on page 20. It's for good reason though - I want to remind myself of some anatomy McGilchrist discusses there, and some definitive pondering he does on its implications. 

The frontal lobes are the "most lately evolved part of the brain" - I guess when he uses the term "brain" in this section, he means the vertebtrate brain. 

VOLUME AND MYELINATION
"Whereas the frontal lobes represent about 7% of the total brain volume of a relatively intelligent animal such as the dog, and take up about 17% of the brain in lesser apes, they represent as much as 35% of the human brain..it's much the same with the great apes, but the difference between our frontal lobes and those of the great apes lies in the proportion of white matter. (Semendeferi, Lu, Schenker et al 2002; Schoenemann, Sheehan & Glotzer 2005). White matter looks white because of the sheath of myelin, a phospholipid layer in which some neurones surround the axons, the long processes of the nerve cell whereby outgoing messages are communicated.  This myelin sheath greatly speeds transmission: the implication of the larger amount in human frontal lobes is that the regions are more profusely interconnected in humans. Incidentally, there's also more white matter in the human right hemisphere than in the left, a point I will return to (Allen, Damasio, Grabowski et al 2003)."

PRESUMED ADVANTAGE
He thinks these great big white, densely intraconnected lobes enable us to "stand back from the world, from our selves, and from the immediacy of our experience", "plan, to think flexibly and inventively", "take control of the world around us rather than simply respond to it passively", gain distance from the world, "rise above" it. 

He describes immediate bodily experience as "the actual terrain in which we live", "where our engagement with the world takes place alongside our fellow human beings", and remarks, "we need to inhabit it fully." He likens this to living along a "horizontal axis." All animals do this.

Even so, "we need to rise above the landscape in which we move, so that we can see what one might call the territory." This is like a vertical axis, something other animals can't do. It gives us "an optimal degree of separation between ourselves and the world we perceive", "necessary distance", helps us understand it. Provides an optimal focal length. 

DISTANCE IS NOT DETACHMENT
"Distance can yield detachment, as when we coldly calculate how to outwit our opponent, by imagining what he believes will be our next move. It enables us to exploit and use. But what is less often remarked is that, in total contrast, it also has the opposite effect. By standing back from the animal immediacy of our experience we are able to be more empathic with others, who we come to see, for the first time, as beings like ourselves." 

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



1. K. Semendeferi, A. Lu, N. Schenker, and H. Damasio; Humans and great apes share a
large frontal cortex. nature neuroscience •  volume 5  no 3  •  march 2002 p 272-6 [full access pdf]

2. Schoenemann PT, Sheehan MJ & Glotzer LD; Prefrontal white matter volume is disproportionately larger in humans than in other primatesNature Neuroscience 8, 242 - 252 (2005) 

3. Allen JS, Damasio H, Grabowski TJ, Bruss J, Zhang W; Sexual dimorphism and asymmetries in the gray–white composition of the human cerebrumNeuroImage Volume 18, Issue 4, April 2003, Pages 880–894

Tuesday, January 01, 2013

Jan 1, 2013 - this and that

Science-Based Medicine blog has been a good tutor for me. This whole operator/interactor distinction came about because of a conversation I was involved in, there, about placebo, years ago, and a comment by Mark Crislip about how contact was stress-relieving and didn't need to be much more than that:
Quote:
“Monkeys, and other animals, groom each other often with a marked reduction in stress. Touch is good, and one doesn’t need to wrap it up in pseudoscientific nonsense for it to be beneficial.” - Mark Crislip discussing reflexology on ScienceBased Medicine blog

Anyway, Science-Based Medicine bloggers also evolve: today Harriet Hall posted this: Beyond Informed Consent: Shared Decision-Making. It pretty much sums up all the tricky elements involved with the medical approach [which started out as purely "operator", but is carefully transforming itself into "interactor"], based on evidence that has come to us by way of neuroscience

It seems to me that nowadays everywhere I see bits of evidence that remind me of Iain McGilchrist's book, and attempts to loosen "left hemisphere-like" control by the culture on thinking by all aspects of human primate social grooming, from SBM to SomaSimple, and who knows where it will all end? Maybe a whole lot of chaos, or a whole lot of world peace, or maybe a whole lot of both in some infinitely far away human or no-longer-human-as-we-currently-know-ourselves future.



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

SOURCES

Operator Interactor, Diane Jacobs, 2011

Beyond Informed Consent: Shared Decision-Making, Harriet Hall, Jan 1, 2013 



Iain McGilchrist: Why Things Are Not What They Seem and the Courage to Think Differently, William Harryman, Jan 1, 2013

EXCERPT:
"Iain was a Research Fellow in neuroimaging at Johns Hopkins Hospital, Baltimore. He has published original articles and research papers in a wide range of publications on topics in literature, medicine and psychiatry. His latest book, The Master and his Emissary: The Divided Brain and the Making of the Western World, published by Yale in November 2009, explores the way in which the bihemispheric structure of the brain influences our understanding of the world.
A vast body of research reveals that the brains of birds and mammals, including humans, have evolved to enable us to apply two equally necessary, but mutually incompatible, types of attention to the world. One is sharply focused, but narrow, certain already of what it will find; the other is broad, open, and receptive to whatever it may find, without preconception. So difficult is it to combine these types of attention in one brain that they have been sequestered to the two distinct cerebral hemispheres. It is the left hemisphere that provides instrumental attention, enabling us to get and manipulate, by focusing sharply on narrowly conceived detail.
It is the right hemisphere that provides what one might call relational attention, enabling us to see the whole picture, to form social bonds, to inhabit and belong to the world we see, rather than simply being detached from it and using it.
Over time there is a tendency for the view of the left hemisphere to entrench itself: it is simpler, more explicit, ignores what does not fit its paradigm and makes us powerful manipulators. But the price is a baffled incredulity when the world does not seem to work the way it would predict. The costs include widespread despoliation of the planet, empty consumerism, a belief in theory at the expense of experience and an unwarranted optimism as we shuffle like a sleepwalker towards the abyss."

The Life of Pi, and Other Infinities by Natalie Angier, Dec 31, 2012