THE EVOLUTION OF THE BRAIN

Steam punk brain

The brain as an organ has evolved in a number of different ways:

Not just a blob

Beginning with the single-celled eukaryote: 

the cell structure of membrane “skin” and 

its attachments and ports (ion gates, cilia for movement), 

the structure of the interior, 

the nature and number of inclusions, “captured” sub-cells,

capacity to create molecules,

ability to detect and use motion to approach food and 
   move away from danger,

ability to exchange genetic material with other cells through
   meiosis

Collaboration with other cells:

Formation of localized structures that specialize in breathing, heart beat regulation, balance, basic motor movements and foraging skills.

These structures become more sophisticated over time.  Newer structures usually form around the older parts rather than discarding them.

An evolved frog

The primitive hind brain (the protoreptilian brain) forms to sustain fundamental homeostatic functions.   Includes the pons which is considered part of the brainstem.  It transmits messages and is the origin point of dreams.   The medulla — sometimes called Medulla Oblongata — is involuntary and entirely unconscious but crucial to life as it regulates blood pressure and breathing.  It helps transfer neural messages from the brain to the spinal cord through the vagus nerve and the autonomic nervous system.  The reticular formation is a set of interconnected nuclei (clusters) that are located throughout the brain stem.

Spatial arrangement:

Arrangements tend to be cumulative from the brainstem at the top of the spinal column forward to the front, but not always, as new additions sometimes require more space and develop in a way that pushes things around.

The cerebrum and cerebellum have a different structure in that they are arranged into cortical architecture, layers with the white (insulated) axons underneath the gray matter.  It is convoluted, as they say, like a dinner napkin crumpled into a wineglass.

Tree of Life

The cerebellum is behind the brainstem and below the occipital lobe of the cerebrum in humans.  It’s interior axon fiber tracts are called the arbor vitae or Tree of Life.  In reptiles and fish it was the pallium before part of it elaborated as follows:  “In mammals, the cortical part of the pallium registers a definite evolutionary step-up in complexity, forming the cerebral cortex, most of which consists of a progressively expanded six-layered portion isocortex, with simpler three-layered cortical regions allocortex at the margins. The allocortex subdivides into hippocampal allocortex, medially, and olfactory allocortex, laterally (including rostrally the olfactory bulb and anterior olfactory areas).” 

Differences in total size were disproven as signalling improvement or uniqueness.  (Men have bigger brains, but that doesn't mean smarter.)  This is a quote:  “Different sizes in the corticol areas can show specific adaptations, functional specializations and evolutionary events that were changes in how the hominoid brain is organized. In early prediction it was thought that the frontal lobe, a large part of the brain that is generally devoted to behavior and social interaction, was the main player in the differences of behavior in hominoid and humans. This theory was dispelled by the test that showed that with damage to the frontal lobe both humans and homonoids [chimps] show atypical social and emotional behavior meaning that the frontal lobe was not very likely to be selected for reorganization. Instead, it is now believed that other parts of the brain that are strictly associated with certain behaviors was where evolution targeted. The reorganization that took place is thought to have been more organizational than volumetric; whereas the brain volumes were relatively the same but specific landmark position of surface anatomical features, for example, the lunate sulcus suggest that the brains had been through a neurological reorganization.

Quiescent child

“There is also evidence that the early hominin lineage also underwent a quiescent period, which supports the idea of neural reorganization.”  This quiescent period is analogous to the “adrenarche” or even earlier time before the adult teeth grow in.  Some call it “middle childhood.”  This is the time of learning social structure, developing culture and identity, and developing speech. These are thought to be the factors that make humans more “fitting” because it is a time of “plasticity” for individuals, a crucial quality of humans who can adapt to a wide range of circumstances.

Evolution of the genetic blueprint

“Two genes were found to control the size of the human brain as it develops. These genes are Microcephalin and Abnormal Spindle-like Microcephaly (ASPM). The researchers at the University of Chicago were able to determine that under the pressures of selection, both of these genes showed significant DNA sequence changes.”  

The Rest of the Body

Clearly, where ever neurons go is a part of the brain, not just accumulating data, but sorting, editing, weighting, even making instant decisions like pulling back a burnt finger.  Much of it is not accessible to consciousness, not even speechless concepts.  But the gut, which has a LOT of neurons and all the organs that send and accept secretions as communication, are “thinking” as directed ultimately by the brain as dashboard.

Pressure from the environment forces adaptation

“The researchers statistically analyzed the key differences between the primate and human DNA to come to the conclusion, that the differences were due to natural selection. The changes in DNA sequences of these genes accumulated to bring about a competitive advantage and higher fitness that humans possess in relation to other primates. This comparative advantage is coupled with a larger brain size which ultimately allows the human mind to have a higher cognitive awareness.”  (More storage.)

So much of our environment is human, pressing on us with violence, stigma, false notions, conditioning, habits, etc. that the brain must devote much more space to all this, esp. since we are living concentrated but imaginary media lives.  There is evidence that individual spindle cells are developing sensitivity to all this, a big example being “mirror cells” which help us “see into” other people.

Attunement

The Future

Natural random mutations are now interacting with human-built structures, economic resources, community requirements, and the natural geological and climatological changes of environments on the planet.  These are pressing evolution in what is probably a mosaic pattern around the world: that is, some brains have hardly changed while others are processing and inventing quite differently.  It’s hard to tell what will be an advantage without looking back over a life.  Schizophrenia may turn out to be very helpful.  Simple endurance may save people in the great wastes of famine.  Machiavellian lack of conscience seems to be an advantage in crowded capitalistic settings.  Evolution only responds to the actual, not the ideal.

Probably much more evolution than we are aware of is happening on the molecular level in food additives, herbicides, gender-related hormones, anti-depression drugs and so on.  In fact, depression itself may be a result of environment pollution that we have created.  But rumors that the government may require the removal of such drugs from sewage systems are frightening because they will be catastrophically expensive.  The main evolution will be speedier destruction of small towns who can’t pay for such amelioration.  And yet, we often think of small rural communities as places that can shape humans in good ways.

Barrels, stripes, and the septa that seperate them likely form as a result of conserved developmental mechanisms that depend on correlated neuronal activity from a sensory sheet to form connections within modules.

WHAT'S UNDER THE SKULL

The human brain is capable of deep ceremonial feeling because of evolution, which created a cumulative set of subdivisions capable of supporting each other, as well as doubling back synergistically to create new abilities.  The physical structure of this sequence that reaches back to paleo dawn-time is based on the upright spine where at the top of the vertebrae is balanced a heavy head between two shoulders that enable the movement of arms to throw, to cradle, to lift.  (Under where shoulders meet arms is a furry place where human pheromones accumulate.  Smell as identity and emotion.  A product.  A sensorium loop.)

The top of the spine, the “BRAIN STEM” has three parts which go back to reptile days.  The three parts are the “Midbrain”  (basic vital life functions such as breathing, heartbeat, and blood pressure),  the “Pons” (sleep, hearing, posture, movement), and Medulla (breathing and heart rate).

The “LIMBIC SYSTEM” is the mammal part where the emotions are rooted and contains  four main parts: 

the Thalamus (Axons from every sensory system (except olfaction) synapse here as the last relay site before the information reaches the cerebral cortex)

Hypothalamus (homeostasis, emotion, thirst, hunger, circadian rhythms, and control of the autonomic nervous system. In addition, it controls the pituitary).  

Amygdala (involved in memory, emotion, and fear. This is a component of the limbic system.), and 

Hippocampus (converts short term memory to more permanent memory, and recalls spatial relationships in the world about us)

The CEREBRUM looks like a shelled walnut.  It is in halves.  Each half has four “lobes” which are named for location: front, back, top, sides, 

 Frontal Lobe- associated with reasoning, planning, parts of speech, movement, emotions, and problem solving

Parietal Lobe- associated with movement, orientation, recognition, perception of stimuli

Occipital Lobe- associated with visual processing

Temporal Lobe- associated with perception and recognition of auditory stimuli, memory, and speech

The NEOCORTEX is the “rind” of the cortex and has six layers, labelled from the outer layers in, I to VI. In humans, the neocortex is involved in higher functions such as sensory perception, generation of motor commands, spatial reasoning, conscious thought, and language.  These layers are the location of consciousness, both one’s ability to feel like oneself, to introspect, to know where you are, to remember consciously, to reflect and reason.

________

It now becomes clear that the prefrontal neocortex, behind and above the eyes, contains specialized cells.  We don’t know what they all do, but they most crucially enable empathy, which is our access to communication and community with other living beings.  Von Economo neurons are spindle shaped cells found only in humans, primates, dolphins and elephants.  There are not many but they are found in the anterior cingulate cortex (the part that wraps around the corpus callosum that connects the two brain lobes) and the frontal insula.   These cells monitor, edit, and respond to perception, motor control, self-awareness, cognitive functioning, interpersonal experience, pain, hunger, realizing a mistake, empathy, trust, guilt, embarrassment, love, responding to infants, recognizing and reading faces, “gut” feelings (intuitions), itching, temperature discomfort, “sense of humor,” and other human “feelings.”   This area has something to do with schizophrenia.

Allman, a researcher, says that it's the link between self-monitoring and awareness of others that makes it possible for us to understand the feelings of other people. "The basic proposition that I'm advancing is the notion that self-awareness and social awareness are part of the same functioning.”  These functions are the crux of what religious institutions try to touch and mold into the institution’s basic understanding of the culture.

But my understanding of the design of deep ceremony is not interested in an institutional point of view.  What this theory of deep experience revolves around is the use of the senses and the neocortex to affect the unconscious parts of the brain and body as it interacts with its surroundings, both taking in information and creating responses. When the conscious, the unconscious, and the entire body is in harmony, then the experience registers deeply.

The chief method of thought in the six layers of the neocortex is metaphorical.  There are two “maps” inscribed on the layers.  One is a simulacrum of the human body with the distortion being that areas that get the most use have acquired the most neurons, most thickly connected, and are represented by being much larger on this mental map.

The other is a kind of GPS system that monitors our orientation in space: up, down, moving forward, going sideways, tipping over, and so on.  It records connections between bits of information.  Most thought metaphors are geometrically organized.  People sketch out little diagrams of their ideas.  Metaphor study is separate from brain anatomy and it is metaphors that are most crucial in the organizing of a ceremony.  (See the work of Lakoff and Johnson).  To make good sense, metaphors depend upon the skillful handling of sense memory and spatial relationship.  

The Gungan Sacred Place on Naboo

The most common deep metaphor (unconscious) for ceremony in Western anthropological terms is that of the Space.  A ceremony is like a room, a place, where it is safe enough to be vulnerable, to share, and to change.  For Victor Turner, whatever is used to take the person’s consciousness into that “space” is a threshold (a limen).  When you go over it, the “space” or “sanctuary” is felt.  (See Eliade, “The Sacred and the Profane”)  Ideally, the physical enclosed space of a church, a temple, or other holy physical place would coincide with the “felt” sacrality of the person’s frame of mind (connectome among the responding neurons).  

If the person visits this “place” regularly -- either as a physical location or as a mental state -- the threshold will be helped by habit, which is a memory function.  Some people simply never manage to achieve this “frame of mind” and will not be able to understand those who do.  Whether this is an unlearned skill or some kind of anatomical defect cannot be known because it is so subtle and so dispersed throughout the brain structures.  But it can be achieved by surprise if the environment, including other people, evokes that “frame of mind.”  This is where the stream of consciousness flows, and it is almost hydraulic in its nature.  Sometimes sheer intensity, as in combat or other moments full of adrenaline (which is a very powerful drug) will push (or pull) people over the limen.  It is linked to intimacy.

Thresholds vary according to culture and also respond to individual experience and temperament.  The task of ceremonial design is to find the triggers that open the doors.  The “deeper” one can empathize with the people present, the more likely to find the assumed, unconscious, ingrained, sense and metaphor triggers that will take the group across the threshold.

Now we can talk about communion, it’s origin and enactment.  You’ll notice that it’s a word similar to community, and therefore depends upon a shared metaphor that is very basic, that of eating and drinking together.  What that shared metaphor means to the persons involved and what they are actually consuming will be linked by their daily lives.  The liturgist who can use that as a poet will be able to touch hearts.  No divine intervention is necessary.

THE BRAIN: A COLLECTION OF APPS

Daniel Dennett is a philosopher and looks prophetic, which suits him fine.  He was the tie-off speaker on HeadCon ’13: What’s New in Social Science.  This is at edge.org, filmed last summer under a lovely awning on a California lawn.  Younger people had previously analyzed and organized amazing new research on what it is to be human.  Incredibly minute and specific work on the organic brain is meshing with the new understanding of culture and cognition.  Dennett’s startling way of saying what I’ve said here before, that the brain is community of cooperating one-celled animal, is calling it the “termite colony captured in the skull.”   

He’s talking about “non-Darwinian” evolution and economies, which I take to mean non-organic, the memes.  He speaks of “foible manipulation.”  One stumbles onto a gimmick and exploits it.  In my own terms, it’s being an energetic seventh grade kid who looks for crevices and advantages in all limitations of his behavior, from things to find out, to things he or she can make the body do, to ways of controlling adults.  In the latest form of computer metaphor, the brain is a collection of apps.

Now -- if that doesn’t make you feel too crawly -- I’m going to jump to another study that is “termite by termite”.  http://www.dana.org/Cerebrum/2014/Mapping_Your_Every_Move_1_/#   By now many of us realize that there are many tiny structures in the brain that have different functions, like the hippocampus manages memory and the amygdala manages both fear and pleasure -- so on.  Now comes the entorhinal cortex, which contains the grid-cell navigation system.  This is a tool for both cognition and navigation, “where you are” in both senses.  

So it must be the source of all those diagrams in books that explain stuff like the structure of sentences as well as being the source of our love of treasure maps, as though we are always “seeking the way to the treasure.”  It also codes a map of one’s memories.  It is an early system that gets knocked out in Alzheimers, resulting in the first symptoms of forgetting and getting lost.  The connection to Alzheimers means it has a high priority for study.

One of the more interesting little exercises at retreats is to ask people to draw that map of “where they’re at” and the history of how they got there, and then to explain it to their neighbor.  This would be even more interesting if one could make it multi-layered by using a computer program or sheets of clear plastic to make overlay maps from different time periods or the interaction of different maps, say one of intimacy versus one of economic achievement.

It turns out that neurons as individuals are of different “kinds” of termite with different duties.  This linked article lists and explains (now that we can detect them) kinds of neurons, “apps.”

“Place cells” are in the hippocampus, GPS notations of where the creature is.  Over time this becomes a dynamic map, constantly updated and not dependent on landmarks, like the GPS screen in a car.

“Head direction cells” record which way your face is, well, “facing,” regardless of what your body is doing.

“Grid cells” are right next to the hippocampus and constantly triangulate location.

“Border cells” signal when a creature is next to a wall or edge.

Quoting the scientists:  “The collective significance of these findings is that the reactions of the neurons can be matched to what is found in the external world. It is still too difficult to trace other types of complex thinking to their sensory origins. Where information is combined across sensory systems, the firing patterns of the neurons involved are too diffuse for us to detect patterns and relationships to what is happening in the external world.”  . . .  

“So by focusing on something more accessible, such as the way space is represented in the brain, we can begin to understand how the brain computes itself, and how external inputs from the senses get into the primary sensory cortex.”

Navigation is one of the earliest skills of the “animal,” a skill a plant does not need since it cannot travel.  Now we have come so far that we are making maps of the brain from the outside, seeing what its topography is and how the electrical messages travel along it.

More quoting:  “The brain’s GPS—its sense of place—is created by signals from place cells to head direction cells, border cells, grid cells, and cells that have no known function in creating location points. Place cells not only receive information about a rat’s surroundings and landmarks, but also continuously update their own movement—an activity that is actually independent of sensory input.

Now the scientists are looking at “speed cells” that tell the creature how fast it is moving.  Also, decision-making cells.  “The neurons involved in this decision-making can be found in the prefrontal cortex, which connects to the hippocampus via a small nucleus in the thalamus.” 

Let me “ground” these ideas with homely examples.  My father grew up on the prairie where travel was via grid systems, dividing flat terrain up into squares like a chessboard -- and he was a good chess player because he understood the patterns that alternating squares present.  My mother grew up in Southern Oregon hill country in the headwaters of the Willamette Valley.  She understood valleys and ridges, landmarks like big trees or patterns of horizon or watercourses.  When my family traveled across the continent, sometimes my father knew where we were -- other times it was my mother.  He knew soils and learned geology.  She knew plants and understood art of a representational kind.  

When it was time for me to start kindergarten, I was escorted to Vernon School once, a checkerboard problem: five blocks up Sumner, two blocks north on 20^th.  I couldn’t remember when to turn north, so I sat down on the curb and wept.  Along came some “big girls” who rescued me.  The last time I went back, a half-century later, I was also confused about when to turn because the trees had aged out and died, the houses had changed, so my landmarks didn’t work.

My father liked to be “on the move,” and one of our favorite occupations on a balmy Sunday evening was to “go get lost.”  Because of his prairie childhood, he found all elevations significant and since Portland was a river valley with volcanic cones and the West Hills, he was pleasantly baffled by the roads that went round, up and over, plus the experience of looking out over the lit city.  The seduction of the “Other.”  If he became a little too confused, my mother knew where we were.  We could see from the top of Rocky Butte or from Skyline, what the layout was.  

When it was time to teach new animal control officers how to follow the maps of Portland so they could go efficiently to the addresses of complaints and emergencies, I found that some of them understood terrain and some did not.  Some only learned by rote, a serious handicap.  In fact, they were people who functioned by obedience rather than by figuring things out, which was a disadvantage in such a free-form job.

Note the love of landscape.

What I’m saying is that when one studies brain function “apps” one is looking at function in the world, how the termites build thought patterns that control everything, and then how their conclusions and actions create a new map overlay that adds depth to the genomes.  Those who have the REAL advantage are those who seek uncharted territories, regardless of what dragons may dwell there.  Those who stick to the maps only have one version of reality.  It might not work.