Saturday, February 23, 2019

THE FACE OF IT

These concepts are from "The Early Development of the Autonomic Nervous System Provides a Neural Platform for Social Behavior: A Polyvagal Perspective" at https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3079208/  by  Stephen W. Porges1 and Senta A. Furman
For more Porges work go to  https://www.ncbi.nlm.nih.gov/pubmed/?term=Porges%20SW%5BAuthor%5D&cauthor=true&cauthor_uid=21516219  or YouTube and use the directory.

These are my takeaways:

We are still discovering major structures in the brain, what they do, what they imply.  

Assumptions mess up research.  The autonomic (automatic, below-sub-conscious) nervous system was assumed to be binary, like all the other fav ideas of Englishmen.  In fact, under the parasympathetic system that we knew was another third one of major importance.  It is a two-step bridge across the last trimester of gestation and through the first three years post-partum.  The first part after birth is supported and regulated by sucking, the first kind of eating.  The second emerges from interaction between mother and infant face to face, as while nursing.  Failure to establish social relationship this way is the reason neglected orphans die -- the necessary neural structure doesn't develop.

The Polyvagal Theory "It is necessary to understand the phylogenetic origins of mammalian autonomic nervous systems to understand how autonomic state is linked to social behavior. This conceptualization has been described as the Polyvagal Theory (Porges, 1995, 1998, 2001, 2003, 2007). The theory was derived from the identification of the two motor branches of the vagus nerve, the Xth cranial nerve, that provides both motor and sensory pathways between brainstem structures and visceral organs. The theory emphasizes not only the phylogenetic shifts in neuroanatomy of the vertebrate autonomic nervous system, but also proposes specific, adaptive behaviors that co-occur with these transitions."

This maturation process emerged from evolution across from reptile to mammal.  Reptile's response to serious danger is just to freeze.  The mammal repertoire includes flight or fight.  These responses are supported by heart rate and metabolisms of specific molecules.  The result is three identifiable circuits that regulate adaptation to challenges.  The newest one is access to learned social strategies.  The basis of social strategy is safety.  The indicator is heart rate, controlled through this vagal "brake" of nerve.  Malfunction is the source of tantrums.

Nerves called "special visceral efferent pathways" are not visceral.  Rather they are about the face, head and neck and are tied to an "integrated social engagement system."

"Specifically, the Social Engagement System includes the regulation of the eyelids through the orbicularis oculi (e.g., social gaze and gesture), muscles of facial expression (e.g., emotional expression), middle ear muscles (e.g., extracting human voice from background sounds), muscles of mastication (e.g., ingestion, sucking), laryngeal and pharyngeal muscles (e.g., vocalizing, swallowing, breathing), and muscles of head turning and tilting (e.g., social gesture and orientation). Collectively, these muscles act as filters for social stimuli (i.e., observing others’ facial expressions and the detection of prosody in human voice), and they allow the expression of the motor behaviors necessary for engagement with the social environment."

This explains lullabies, which are meant to develop the "middle ear muscles (e.g., extracting human voice from background sounds)"

"Prematurity, illness, or neglect may dampen the developmental trajectory of the vagal circuit. Atypical maturation of this circuit may be reflected in myelination of the vagus, interneuronal connections in the brainstem that form the face-heart connection, and/or corticobulbar regulation of the brainstem circuits regulating both vagal activity and the striated muscles of the face, head, and neck. The consequences of these delays or disruptions in typical neural maturation would be expressed as lower levels of RSA, less efficient reactivity and recovery of the “vagal brake,” difficulties in behavioral state regulation, poor affective tone, and diminished abilities for reciprocal social engagement behaviors."

In short, the writers are able to put in place the interaction of tissue development and nurturing as the beginning of the expressive-ability of an individual that will help him or her become an integrated part of society.  Not only that, specific physical measurable tests and standards are suggested in order to discover whether there is a shortfall.  It is a hopeful stance because of the suggestion that there are many ways to improve.

"Social behavior and the capacity to manage challenge are dependent on the neural regulation of physiological state. The neural circuits involved in the regulation of physiological state are modified during gestation and continue during postnatal life. When these circuits are easily available and efficiently functioning, then the laws of learning and the impact of experience can shape behavior. However, when these circuits are not available, either as a function of phase of development or during periods of increased environmental risk, then state regulation is compromised, social skills are not easily learned, and social bonds become difficult to establish. During most of the lifespan, the vagal brake and the other features of the Social Engagement System are readily available and contribute to the numerous opportunities for social learning to occur. Without the efficient vagal brake turning off defensive systems and blunting their disruptive manifestations (e.g., fight-flight behaviors), prosocial behavior is limited and opportunities for social learning and social bonding are minimized."


This research supports much of the work I've followed as it happens among the Smash Street Boys.  It evades conventional morality and goes to things like finding and maintaining pair-bonding, taking a place in an identified social circle, facing challenges, and calming oneself after a challenge.  Much of the photography is about faces, the "integrated social engagement system."

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