By now you know that I read a lot of brain stuff. I still have not learned the names of all the parts, but I’ve learned enough to know that it’s not a matter of BOXES, but rather a matter of BUNDLES: bundling of kinds of parts, supports, renewal, work-arounds, and connections to other bundles. Here are two long quotes from nimh@public.govdelivery.com which is doubling-down on brain issues. The goal is to do for the “connectome” (the networked bundles and their relationships with the other brain bundles) what has been done for the genome with such enormous consequences.
“A team of BRAIN Initiative-supported scientists, led by Arnold Kriegstein of University of California, San Francisco, reported in Cell, Sept. 24, 2015, on what may be the secret to the human cortex’s exponential growth.
“Kriegstein and colleagues found that the human cortex harbors a unique support system for neuron-producing factories during early brain development — in outlying cellular neighborhoods that barely exist in lower animals. The researchers discovered the molecular underpinnings of this unique group of stem cells that churn out thousands of neurons and support cells where their mouse counterparts produce only 10-100. They also discovered that the secret to this prolific output seems to lie in these cells’ ability to carry with them their own self-renewing “niches,” — support systems that enabled them to thrive in far flung circuit suburbs. The results add to a deeper understanding of the human brain’s parts list and enhance scientists’ ability to perform disease-in-a-dish experiments relevant to uniquely human disorders like autism and schizophrenia, which are difficult to model in rodents.
Another team led by Stephen Smith of University of Oxford, UK, and David Van Essen, Washington University, St. Louis, explains findings linking brain connectivity to measures of personal success Sept. 28, 2015 in the journal Nature Neuroscience.
Smith’s group mined Human Connectome Project data on 461 individuals to find out whether any patterns of brain connectivity are associated with specific sets of correlated demographics and behavior. In addition to images of their resting state structural and functional brain connections, the Project collected data on 280 such subject measures, including psychological factors such as IQ, language performance, rule-breaking behavior and anger. A set of such measures statistically related to each other emerged as strongly correlated with connectivity between certain brain structures prone to talking with each other during the brain’s default mode, or resting state. This set was mostly composed of positive personal qualities, such as high performance on memory and thinking tasks, life satisfaction, years of education, and income. The set turned out to have a more than three-fold stronger correlation with increased brain connectivity than any of 99 other sets of measures examined. The brain regions associated with the set, which may be related to general intelligence, have been linked to higher-level human thinking – e.g., memory, imagination, sociability, value-guided decision-making and reasoning.
Smarts, life satisfaction, income and education levels – and other measures of success – were correlated with increased connectivity between certain areas of the brain while at rest. These parts of the brain (yellow, red, brown) talked with each other more while higher-scoring participants weren’t doing anything in particular. Picture shows composite data from functional magnetic resonance imaging scans.
This fits well with the ideas about each specialized sensory organ (ear, eye, tongue, etc) having a support platform of neurons that organizes and edits the raw electro-chemical codes of perception before sending the result to the “master work platform” which is a sort of dashboard that manages all the sensory input into a “bundle” of about seven or eight concepts, which is the limit of about how much information it can process at once. Then it guides whatever is done, whether turning one’s head, bending over, or running like hell.
It also fits with the ideas about the whole body being a sensory instrument, feeding in unconscious detections as well as deliberate ones. But it works against one-blob ideas of the brain as organ while justifying those amazing derivations of what messages are going where at any given time, the shifts of which tell us when to go to sleep, who we are, what we should do next, whether we like chocolate.
Perhaps because of the shelly hard-ness of the skull, which suggests confinement as much as protection, the brain has been seen as a “black box,” which is also symbolic of mystery. Eurasian culture likes boxes, builds square rooms, and uses them as protection for precious things.
But bundles are the way the Americans group things, wrapping them in soft hides or at most putting them into a rawhide quiver or envelope. This is a sign of being organic -- no metal -- and traveling with animal power. Lodges are built round except for the cliff dwellers whose boxes are stone and stucco, rounded, and the NW cedar plank houses are inside organized by round fire sites.
As a relating connection, think of liturgy, a word related to ligatures, and suggesting the bundling of objects or tying things together. CSI shows talk about strangling or bondage, limiting by binding, as being done with ligatures. A story about sticks is the father who takes up a slender stick and easily breaks it in half. Then he takes up a handful of the same-sized sticks and tries to break the bundle, but cannot. It’s a lesson about sticking together, strength in cooperation.
If a brain is a bundle of elements and processes, then it’s probably possible for the bundle to go on functioning in some fashion with one or another “sticks” missing, though the bundle is weakened. If too many elements are missing or broken, things will go wrong in different ways, depending on what is missing or not operating.
But a brain is not just a connectome of "wiring." It is also bathed in fluid, a kind of filtered fluid that blocks out the biggest molecules, which are often poisonous. Nevertheless it has molecules that it makes and sends to the rest of the body and they are integral to thought and mood. I’m talking about things like serotonin. I was surprised to learn that some of these in-body products are excluded from the brain, so I need to figure that out. The reason is always couched in terms of mutations that are an advantage, rather than simple survival, but the simple fact is that any change that is a hindrance can cause death, extinction. The body is always editing, editing, editing -- not individually but en masse. But then if the larger situation changes, what was edited out might be the very thing that could save people now.
One of the values of seeing the brain as a bundle of elements is that it’s easier to understand that functions come online as they develop in terms of cell capacities and structure. If they are hurried or denied, which often happens with abuse, then the bundle will not function as it would if it could develop in its own time. Maybe some components will be slow, but might still arrive eventually if there is enough protection to survive until then.
Culture is also a bundle and so is an ecology, where things that don’t fit are also simply snuffed, sometimes sending consequences into the human body. Lack of iodine crippled the development of whole Chinese villages, creating a generation of brain-crippled people. My own grandmother had a goiter from lack of iodine, often a problem with inland people. It was treated by moving to Portland, Oregon, and eating sea food. Now, of course, our household salt is iodized. If the doctors had known about this, Charlie Russell’s life would have been much extended. He died of goiter-related heart disease. But he refused medical treatment, something he learned from watching people in the hands of doctors in those days.
Goiter in the Andes, where the folk remedy is seaweed.
Our morphing culture is revealing new things almost faster than we can absorb them. But there are many elements to ferret out and learn about, like hatred and prejudice and bullying and abuse and the neglect of the weak and needy. The sorting of sticks continues.
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