These many recent breakthroughs about how neurons work are possible because now we have the ability to look at one cell at a time, to see messages go slipping down the axons to the next cell, to figure out what’s happening to the molecules in the cell, even which atoms of the mitochrondria are going on walkabout and what it means when electrons jump. We know now that the neocortex is six layers thick and the layers are connected through and through by columns. Only mammals have this, but ALL mammals have this. All mammals have that neocortex wrapped around the brain. Only humans have a PRE-FRONTAL neocortex behind their forehead, over their eyes.
But recently, by being able to describe cell by cell, the scientists have figured out that birds do have neocortex, but it’s not in sheets wrapped around the rest of the brain. If it’s a matter of how many neurons they have, they’re smarter than monkeys, so numbers can’t be the whole story.
“Both the mammalian neocortex and a structure in the bird brain called the dorsal ventricular ridge (DVR) originate from an embryonic region called the telencephalon. But the two regions mature into very different shapes, with the neocortex made up of six distinct cortical layers while the DVR contains large clusters of neurons called nuclei.”
It appears that one little nuclei of neurons is what enables birds to sing, and the premise is that an equivalent, possibly “Broca’s brain”, is the same thing in humans and enables us to speak. Our words are songs.
“A similar experiment was conducted in a species of turtle, and revealed yet another anatomical possibility for neocortex-like cells. Instead of a six-layer neocortex or a cluster of nuclei, the turtle brain had layer 4- and 5-like cells “distributed along a single layer of the species' dorsal cortex.
If turtles had that little nuclei, perhaps they could sing, but the Song of Solomon meant turtledoves. There are no singing reptiles. Right?
Brains are cumulative — that means that the old brain versions are not discarded when new ones develop, but rather the old parts are kept whether changed and newly useful, or simply there, or interfering. The connecting filaments wind back and forth through old and new.
Brains are ecologies, not homogenous tissues but clusters of specialized but communicating cells, some grouped into organs and others as independent as the original eukaryotic one-celled animals we came from, still capable of telling which direction is forward and what the environment tastes like.
I don’t understand this passage, so I’ll just note it and leave the wiki-links. “There are two types of cortex in the neocortex, the proisocortex and the true isocortex. The pro-isocortex is a transitional area between the true isocortex, and the periallocortex (part of the allocortex). It is found in the cingulate cortex (part of the limbic system), in Brodmann's areas 24, 25, 30 and 32, the insula and the parahippocampal gyrus.”
So far what I get about a lot of brain stuff is that they can tell the little bits are subtly different and sometimes what they do, so they just label them to make a way of talking about them. “Archicortex is a type of cortical tissue that consists of three laminae (layers of neuronal cell bodies). It has fewer layers than both neocortex, which has six, and paleocortex, which has either four or five. Because the number of laminae that compose a type of cortical tissue seems to be directly proportional to both the information-processing capabilities of that tissue and its phylogenetic age, paleocortex is thought to be an intermediate between neocortex and archicortex in both aspects, and archicortex is thought to be the oldest and most basic type of cortical tissue.”
So now I’m going to say that ideas are just big echoes of brain tissue; first we label, then we guess, then we test -- often by ablation which means destruction. The brain is limited by the size of the skull, the turtle is limited by the size of its shell, and people are limited by the boundaries of their experiences. My visitors over the past couple of weeks were all friends in the Sixties when I was in Browning. Unlike the people in Valier, who are full of fantasies about the rez except for those who moved here after years there, these friends had real experience in the same place, but a time long ago, a time that amounts now to a far distant place.
We all left for various reasons, some of us continued to cross paths in Portland or maybe just on the Internet, and so our constructed idea-shells are quite different. As it turns out, because since 1999 I’ve deliberately limited myself to this little house lined with binders of writing and books for reading, I’m probably the most different. Some of the characteristics that I have strengthened for writing, are not good for socializing. For instance, my rigid daily workflow or my long chains of logic and failure to pause for response. Hard on conversation. It seemed to me that they just didn’t believe much of what I said. They were urban-suspicious, rejecting of difference, and echoed the conventional media, though it's the subset for educated urban people.
Portland, OR
They don’t care to know all this detailed stuff about the brain or thinking. Why should they? They cling to the world of our college years when there was science over here and humanities over there and “religion” was anything it said it was. They still think "church." All these friends are writers in a passing way, but still are totally naive about the developments of print and publishing over the past decade. When I get intense about it, they ask what I’d like for dessert.
But somehow that culture — polite and limited, competent but not quite informed, charming but exasperating — must be wrapped around by layers of the one I live in — not the one represented by a physical town, but the one built since 1999 out of ideas as they evolved into an ecology of premises, many of them created out of the destruction/conversion of dyads from oppositions into interacting continuums. My ideas are worrisome, full of danger, crossing into taboos they’ve skirted all their lives, while using secrecy as a shield. They think I’ve been hoaxed.
The Pearl District
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