Evolutionary tidbits

To reiterate my understanding of the biological roots of our humanity, I see human empathy as something special and it laid the foundation for symbolization and that enables us to think and talk about everything and nothing and to create it if it is not already there in reality.  Through our empathy we humans are keenly aware of another’s mind, that they have subjective considerations, and how we can interact with each other mindfully.  Symbols carry this social effort forward with scope and power.

This empathic capability is centered in the right hemisphere that processes kinesic communication and maintains Empathy Central in the temporal-parietal junction where knowledge about our relationships contributes to what the academics call ToM (theory of mind).  Anyway, my thought is that this keen sensitivity to others’ minds became integrated with our mirroring capabilities, so that certain actions could be replicated readily upon observing them in another.  This replication of mirrored actions comprises the invariant forms of social communication, and when our mirroring system came to include vocal signals, so that we could hear a conspecific vocalize/verbalize and reproduce that sound and not just the objectively observable motoric behaviors, e.g., lifting a cup to drink.  This is the functional significance of the arcuate fasciculus on both the right and left sides, but especially on the left, where the af enables the repetition of what we just heard another say (see my post of 4/24/2014 on the arcuate fasciculus and mirroring).  Putting together, i.e., integrating, the awareness of another’s mind and the knowledge produced by the mirrored invariant behaviors led to symbolization, at first linguistic and then artistic (ask me to explain that sometime).  Symbols, if you remember, have a deep structure (what resides in our minds subjectively) and a surface structure (what we use to formulate and then communicate those subjective musings), and voila! language, art and the cultural wealth of our kind.

That said, I have been reading Georg Striedter’s Principles of Brain Evolutionand find a couple of evolutionary tidbits that help to carry my speculative imaginings forward (and I find nothing so far contrary to this path). Consider that human eyes are almond shaped and that our irises are surrounded by white sclera while the eyes of other primates are round and the irises surrounded by dark sclera (though the sclera hidden within the eye socket is white.  Striedter interprets this to show that we humans monitor each other’s gaze and so gather more information about the other’s subjective musings; further that our eyes’ structure facilitates this with its almond shape and white sclera shows that such kinesic communication is important evolutionarily. I see this as an example of our keen awareness of the other’s mind.

Think of some examples of this.  Parents follow the gaze of pre-verbal infants and move to facilitate their exploratory activity.  As Michael Tomasello explains, joint action is a critical advance in our social coordination and eye gaze is an important means by which we cooperate, e.g., one holds something still while another performs a more intricate action such as a nurse clamping a wound while another stitches it up, or one hunter with a bow shifting gaze to match another’s and finding prey.  Finally in this regard, in my early career I learned about the challenge of hearing impaired children (and adults) who must watch the other’s hands to communicate about a task that needs to be seen to be learned. Eye gaze is important in juggling these gaze shifts and we humans have extra talent for this.

Father child

joint gaze and joint action

Streidter also discusses the size of our brains in absolute terms, compared to our body mass, relative to other animals, the amount of cortex relative to the medulla, etc.  He points out that large brains are ‘expensive’, e.g., they require high protein diets, they pose problems for live births due to mismatch between skull size and birth canal, and they pose challenges to communication between neural areas.  This last comes about because areas farther away take longer to communicate with each other and that poses a problem for timing.  Much of our neural processing depends upon the simultaneity or temporal match of parallel processes.  Our brains have evolved with some work-arounds such as long, thicker nerve tracts that nerve impulses travel along faster than thin fibers.  Our brains have many more modules and these connect especially to those nearby with some longer fasciculi, e.g., the arcuate fasciculus, the superior longitudinal fasciculus, the claustrum and the corpus callosum, bearing the burden of longer range communication.

Sobo_1909_670_-_Uncinate_fasciculus

The arcuate fasciculus is part of the superior longitudinal fasciculus. Thicker axons help nerve impulses travel long distances faster.

Now here is another interesting tidbit.  Our corpus callosum is relatively smaller than those in other primate species, i.e., our cerebral hemispheres are less connected than might be expected.  Streidter says the data show that the human brain is more asymmetrical than other species’ brains; this works because our two hemispheres specialize in different functions (yes, even as they perform much of the same functions, one leads, and while brain damage when young can be compensated for, damage when older is less so because the specialization has become at least partially irreversible). Again this difference in connectivity is relative; I have posted here before that studies of our connectomes show females generally have more bilateral connections, i.e., they make more use of their corpus callosum, while males have more connections within each hemisphere than between.

corpuscallosum

corpus callosum with part of right hemisphere cut away

Now this bit of information speaks to two issues.  First is that females and males (please remember that I use the terms in a relative manner and appreciate all manner of androgeny in our variations) approach interactions differently.  This is especially noticeable in preschoolers where girls are both more verbal and tuned into relationships and boys are somewhat less verbal and their attunement to others is, shall we say, less robust.  Actually, talking with my 30 something daughter and others, this difference may even be accentuated in mature humans (maturity, again, is a relative term, guys).  In any event, the functioning of the connectome when emphasizing social and linguistic information together would use the corpus callosum more fully and that would correlate with a female sort of pattern.

The second issue here goes back to my thesis that symbolization arose from, first, the integration between the keen empathic apprehension of another’s subjectivity and the invariant behavioral forms that operate in mirroring, and then, second, once the connections are formed, their separation into the surface and deep structures of our symbols.  Human brains are more asymmetrical and this I associate with the differentiation of function between Empathy Central on the right side and linguistic functions on the left, e.g., one side is pragmatic and the other syntactic/semantic.

The last tidbit comes from Streidter’s analysis of the human brain’s enlarged lateral prefrontal cortex (adjacent to motor and premotor areas) primarily on the left side.  This relatively species-specific area serves, Streidter hypothesizes, our abilities to use our hands and words in very flexible, facile, novel and unconventional ways.  We are able to do things hitherto unseen, un-imitated and even unimagined until we do them.  This includes our words as well as our hands.  This highlights one of the great paradoxical strengths of our language. We use words, conventional symbols with socially established meanings, to say many things that have never been said before, i.e., they are novel and unconventional.  We do this day in and day out in small and large ways for mundane and profound topics.  Back in the day Noam Chomsky focused on this generative capacity to demonstrate the theoretical poverty of behaviorism, and we are still learning about this today.

Lobes_of_the_brain

lateral prefrontal is in lower blue area towards the front

So a long post.  Funny how tidbits expand when I am (you are too hopefully) having fun and learning about our humanity, eh?  Travel on.

Neanderthal update

I like Neanderthal stories for two reasons. First, this research shows science at it best in the development of technologies to date artifacts, the diligent search for ancient clues, and especially, the fact that our conception of who the Neanderthal were has dramatically changed as new data have come in. Since their discovery over a hundred years ago we have gone from thinking them brutes barely different from gorillas to now almost completely human like us. Changing minds through new data is to be much appreciated. The second reason is that genetic studies prove that my ancestors mated with them and I do not want to think of my people long ago mating with brutes of little intellects and no symbolic capabilities. I would hope they were more discriminating.

So the most recent update comes from this story in the NYT: https://www.nytimes.com/2018/02/22/science/neanderthals-cave-paintings-europe.html.

Evidently some paleoanthropologists were holding up their admission of the Neanders into full humanity because they said the evidence allowed the possibility that their use of tools and their art making were copied from Homo sapiens. That objection has now fallen as art and tools have been found and dated through new, refined technology to time periods way before modern humans entered Europe. Hmm, maybe Homo sapiens copied tools and art from them?

My latest thinking on the inception of symbolic thought, both discursive (language) and presentational (art) forms, is that our heightened empathic abilities led to a rather robust intimacy, a mind to mind connection through kinesic modalities wherein we sensed and knew the other’s subjective mental domain, coupled with the increasing power and specificity of mirroring systems serving communication (think arcuate fasciculus). This yields the view that an intimate connection of immediate sensing of another’s mind coupled with the invariant structure of surface behaviors produced the first symbols.

In this light consider why early art is so often found in caves, and not just close to the entrances but sometimes way back in there. We visited one site in France where an electric railcar took us maybe a mile back into the cave to see etchings of mammoths and other animals on the ceiling. Why? Some say that art rose in association with animist magic, that these paintings were a mystical participation with the animal spirits and communion with Gaia. Read Kim Stanley Robinson’s excellent novel Shaman to see the truth of this possibility. But magic has both public and private aspects. Yes, shaman protected their mysteries (and for good reason because sometimes they were not so mysterious once initiated) but they also performed public rituals. Indeed, magic would not be very useful if not public.

Here’s another thought: Art came about when the need arose to extend intimacy beyond the circle of familiars, art being a personal expression of some vital experience, and so the first artists were a bit shy about their productions and protected their privacy by painting deep in caves. As we learned more about art and more came to appreciate the beauty therein, we moved it out into the public domain and cultural identity took on another feature. Even today while some artists open their studios to audiences, many keep their creations private until complete, and some, like Leonardo da Vinci, keep their most precious pieces in their possession. Leonardo kept the Mona Lisa with him for 20 years, working on it a little bit now and again, and died with it in his room, never giving it to his patron. Personal, private, it was.

Anyway, I really like my hypothesis about the inception of art here; it feels fit to me, this combining empathic intimacy and mirrored communication. (You heard it here first). Time, now, to travel on.

Neanderthal_280_470743a

That sapiens guy copied my bison drawing. Good grief! Did a good job though. These new kids may have some talent.

More about musical import

Remembering that Susanne Langer called the symbolic information conveyed by art “import” in the effort to differentiate it from linguistic “meaning,” I read with great curiosity a chapter in Origins of Music, which I am close to finishing. In his chapter, “The Question of Innate Competencies in Musical Communication,” Michel Imberty uses language and conceptualizations strikingly similar to Langer’s in Feeling and Form, though he appears not to be familiar with her work. Consider his statements that he defines the macrostructure of music as a “schema of time,” or that music and dance “are ways of feeling—of being with—before being emotions” or identifying the artistic impulse as “something that weaves itself and makes meaning in time.”

Now compare these to Langer’s conceptualizations that I have written about here over the past several weeks in my Re-Reading 4.0 series.

-the primary illusion of music is the sonorous image of passage

-musical duration is the image of what may be termed “lived” or “experienced” time

-the semblance of this vital experiential time is the primary illusion of music

-the most important and novel revelation of music—the fact that time is not a pure succession, but has more than one dimension  [my favorite]

-the commanding form is not essentially restrictive, but fecund

-the great moment of creation is the recognition of the matrix [commanding form].

I could go on and on with these but better for you to read Feeling and Form, especially chapter 7.

Imberty based some of his analysis on work by Michael Stern, a well known researcher of infant/child development, especially two concepts. One is the “vitality affect” which are feelings before they coalesce around recognizable and conventional emotions, feelings more concerned with dynamic properties such as tension, resolution, building, diminishing, etc. These are the very feelings upon which Langer built her philosophy of art. That Stern discerned these in infants is important—more later. The other one is the “proto-narrative envelope” that “constructs the narrative of time, clarifies the reality of human becoming.” It is the matrix that “makes something weave itself and assume meaning in time.” And this too is important for Stern to have discerned in infant development.

music-notes

So we have here a view of musical composition that begins with an intuitive gestalt (commanding form or protonarrative envelope) formed or abstracted from one life’s experiential passage and then completed with elements (vitality affects or symbolically rendered elements of sound representing those affects) also therefrom.  Listening and appreciation of this artistry would involve recovering some of the form and elements, though not through some inverse process because lives are disparate and complex. Both the composition and recovery is the beauty of symbolic processing whereby minds share information about their experiences.

And the importance of infant development here? Stay tuned for the next exciting episode, “Theta moments, the completion of compositions, and cortical fasciculi” coming soon to this blog.  You can’t get there if you don’t travel on.

Conversation, music and novelty

In my 2/14/14 post I talked about the hippocampus, an evolutionarily older area of cortex.  Information from posterior perceptual areas flows through the hippocampus, which processes it for context and novelty, then sends the results forward.  A good example can be seen when a cat hears a noise, freezes and orients to check it out, and then moves forward figuring what the new situation is.

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Novelty is more complicated than might be supposed.  Perceptually it is detected when something changes or when something expected to change doesn’t change as expected.  The change may be about something static, e.g., an object, or dynamic, e.g., a stream of sound or passing scent.  Something uninteresting may change because of changes within the animal.  Figure may become ground or vice versa.  Perceptually we respond to ambient energies but that response is a very creative task.

Now we return to the 3/30/14 post about conversation.  The left side processes the semantic, syntactic, and phonemic information of a sentence while the right processes the intonation or the prosody of the utterance.  What comprises novelty here is made even more complicated because we are creating the information as we make meaning, because the grammatical and pragmatic information pose different challenges but must be integrated, and because of the rapid and ephemeral exchange composing the communication.

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Maybe the hippocampi, right and left, are involved in this, but more likely higher cortical areas come into play as we understand a comment on a topic and then make our own new comment and then carry on, maybe even changing topics again while monitoring the interpersonal prosody for such things as changes in tone for sarcasm, excitement, joy, sorrow, etc.

An interesting feature of this processing comes when considering H. P. Grice’s 4 conversational maxims of quantity, quality, relevance, and manner.  Briefly, when conversing we expect people to say not too much or too little, to be clear, to be on topic and to be genuine.  These are probably not so much maxims as dimensions shaped by assumptions, so that when we detect a violation, that constitutes novelty.  When we hear a crash from the next room and ask our child what happened and he answers, “Nothing,” that is too little.  When someone goes off topic or becomes tangential or speaks unclearly or sarcastically or (we suspect) disingenuously we may interrupt and intervene to further successful communication.  Novelty of a different and rarefied sort.  Now on to music.

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Daniel Levitin in his book, This is Your Brain on Music, explains how new and old patterns or gestalts are important for music on several levels.  Different cultures have different musical keys which set up our expectations.  The progression of notes and tempo set up expectations which a skilled composer can exploit in order to express different feelings or concepts.  Our memory is important in catching on to the variations of themes.  A performer’s musicality depends in part upon their ability to vary timing and emphasis, etc., a fresh counter to the staid black and white score.  So novelty comes in various forms and guises, each important to the communication of symbolic import through the specialized channels of the MEMBRAIN.   Now this is getting interesting.  Next up?  Either my quibbles with Levitin or an introduction here to the arcuate fasciculus.