A&O – PHYSIOLOGY – BRAIN – exemplary circuits


13 c. medieval medicine – veins



The Brain

Physiology emphasizes the continual dynamic flux of countless interacting processes — it is the grand mobile of our being.

INPUT of information, INTEGRATION of information with past & potential future experiences, OUTPUT in actions that are hopefully adaptive.

The Human Nervous System.  What cannot be explained is described; Wikipedia is a good place to start [link].  With an anatomical overview, we can begin to see what structures are available to enable or implement the processes that allow us to function in the world.

The path I’ve adopted is to look at the behavioral patterns with which we are more-or-less intimately familiar or interested.  Dig as deeply as we care to until we have come up with ambiguities and unknowns.  Understanding, of course, that the deepest insights come from an view that integrates what we may know with confidence about the development, ecology, evolution, and physiology that converge on any specific behavioral pattern.

Two circuits –that is, groups of neurons that function in specific ways and are connected to each other with pathways that excite or inhibit their contributions to a specific behavioral papttern, are PARENTAL BEHAVIOR an ARTISTIC BEHAVIOR.


The human brain contains billions of well-connected neurons. Neural neighborhoods perform different tasks: Some coordinate movement, whereas others hum along planning dinner. The mature brain is a complex assembly of networks, structures, and tracts. Like cities and their neighborhoods, however, the brain does not arise fully formed. Rather, operational patterns and developmental constraints guide the proliferating neurons that build the typical adult human brain. Just as cities are governed by both hard and soft infrastructure—e.g., highways channel traffic and laws define what sort of building can occur and where—the placement and function of neurons in the brain respond to multiple cues during development. In this special issue, we look behind the scenes of this elaborate process that places each neuron where it belongs or—sadly, in the cases of neurodevelopmental disorders—does not.

Generation of these neurons, along with the equally numerous accessory cells, requires enthusiastic progenitor cells. Early in development, straightforward proliferative programs morph to produce diverse cell types. With shifting cascades of transcription factors, each newborn neuron is shaped by its unique time and place.

Glia, originally viewed as bystanders in neurodevelopment, are now known to be quite the opposite. Radial glia are builders of both neural neighborhoods and highways along which neurons move. The immune system, once thought to be excluded from the brain, is also crucial to brain formation: Microglial cells regulate circuit formation and convey physiological information. Evolution constrains development according to successful precedents. Think about that with your marvelously formed brain.” (Pamela J. Hines (2018) Mind-boggling brain development.  SCIENCE  12 OCT 2018 : 170-171.)


Carefully balanced  functional units that are integrated with each other at several different levels of organization:  A very broad and compelling sense of the interaction of multple units working together comes from considering the two hemispheres of the brain, understood after they are separated from each other:  Read Wolman’s news article from the journal NATURE (it includes a good account of split brain research that provided these insights)… (including comments by a split brain patient and an old (1970’s) short video of early research nicely explained–and not much has changed)


  • CIRCUITS and CENTERS that orchestrate specific behavioral patterns are a primary target of the physiological ethologist–indeed, anyone seeking to understand the proximate causes and consequences of behavior (the physiology part)?  Any behavioral patterns sufficiently well described (the ethology emphasis) becomes the basis for  search for its causes and consequences.  AS EXAMPLES: 



  • “Circuits for Care” –essay on brain control of parental behavior by Johannes Kohl (Science  12 Oct 2018: Vol. 362, Issue 6411, pp. 168-169.  DOI: 10.1126/science.aav1249 )  (Article:  Raising a child to independence requires an estimated 13 million calories (1), near-constant attention, and the ability to survive on little sleep. Because parents perform this monumental task without any immediate benefit, it has been suspected that parental behavior relies on evolutionarily sculpted neural circuits. What do we know about the neural basis of parenting?  …  READ Kohl’s ESSAY



  • Excerpt from Reductionism in Art and Brain Science (Chapter 13)
  • Art reaches Within: Aesthetic Experience, the Self, and the Default Mode Network (Vessel et al. 2013)   (“The DMN activity therefore suggests that certain artworks, albeit unfamiliar, may be so well-matched to an individual’s unique makeup that they obtain access to the neural substrates concerned with the self—access which other external stimuli normally do not get. This mediates a sense of being “moved,” or “touched from within.” This account is consistent with the modern notion that individuals’ taste in art is linked with their sense of identity, and suggests that DMN activity may serve to signal “self-relevance” in a broader sense than has been thought so far.”)
  • Beauty and the Brain – A&O READING by Jacobsen (2009) (“Aesthetic appreciation has many determinants ranging from evolutionary, anatomical or physiological constraints to influences of culture, history and individual differences. There are a vast number of dynamically configured neural networks underlying these multifaceted processes of aesthetic appreciation.”)


§  neurofiction essay (Gary Marcus recent essay,  “Neuroscience Fiction,”  in the New Yorker (Dec 2, 2012)