Friday, November 29, 2019

Brooks on Gut

Maybe young Mrs. Brooks is spending Thanksgiving with her family and Mr. Brooks is on his own in Capitol Hill,  because today's column ("The Wisdom Your Body Knows"), which looks like outtakes on the book Brooks had a contract to write before he discovered humility and decided to write something different, has a ton of references to work on neuroscience and none of those helpful links that somebody's been inserting for him recently.
This has been a golden age for brain research. We now have amazing brain scans that show which networks in the brain ramp up during different activities. But this emphasis on the brain has subtly fed the illusion that thinking happens only from the neck up. It’s fed the illusion that the advanced parts of our thinking are the “rational” parts up top that try to control the more “primitive” parts down below.
So it’s interesting how many scientists are now focusing on the thinking that happens not in your brain but in your gut. You have neurons spread through your innards, and there’s increasing attention on the vagus nerve, which emerges from the brain stem and wanders across the heart, lungs, kidney and gut.
Which made me wonder if he was finally starting to discard his traditional Cartesian dualism and accept that the mind is a function of the body rather than a distinct aetherial thing. Which I can't say he doesn't do, since he doesn't use the word "mind" anywhere in the column, or "cognition/cognitive" either, though he does talk pretty freely about the brain doing or sharing the doing of the "thinking". He mainly seems to have temporarily displaced the discussion of mind-body into an alternative discussion of brain-gut and an interest in who, brain or gut, is in control here, which may amount to the same thing.

The increasing attention on the vagus nerve, the longest nerve in the body, cascading from the bainstem down the back to the gut in a dorsal branch and down the front to the organs over the diaphragm in the ventral branch, would be mainly in some communities and not others, starting with the psychiatrist Stephen Porges, who proposed his "polyvagal theory" of what it does in 1994:
Polyvagal theory articulates three different branches of the autonomic nervous system that evolved from very primitive vertebrates to mammals. And it’s quite interesting how the sequence evolved. First, you have a system that is really an ancient one, which is death feigning or immobilisation. Then it has a fight or flight system, a mobilisation system. Then finally, with mammals, you have what I call a social engagement system, which can detect features of safety and actually communicate them to another. When you trigger feelings of safety, the autonomic nervous system can help health restoration. In terms of dealing with a life threat, you most likely go into this feigning death, dissociative state. (Porges interview in The Guardian, June 2019)
The dorsal branch vagus connection from the gut, says the theory, drives the syncope of the gecko or hedgehog and an analogous human response to trauma, that of becoming emotionally numb and immobile (analogies aren't evidence); the ventral connection to the heart drives the mammalian "fight or flight" response or, conversely, acts to soothe the organism and allow it to interact calmly with the environment; and the further ventral connection on top of the lungs to the vocal apparatus regulates sociality:
If there’s exuberance coming from the upper part of a person’s face, and their voice has intonation modulation or what’s called prosody, we become attracted to the person. We like to talk to them – it’s part of our co-regulation.
So when we become polyvagal-informed, we start understanding not only the other person’s response but also our responsibility to smile and have inflection in our voice, to help the person we’re talking to help their body feel safe.
I personally feel there's a little bit of a weak point here in the way Brooks interprets the theory, in that in order to find out whether you want to faint, run away, or smile and speak expressively at a given moment depends on the information the brain is getting and interpreting on the basis of input from the sensory system; there's no way the gut can make that determination without communication from the head. Actually a big weak point. So no, the gut isn't in control of anything, and them frontal lobe of the cerebral cortex isn't either, or the emotional center in the hypothalamus, and the larynx doesn't drive the forebrain language centers either, in spite of Mose Allison's great song.
Maybe you walk into a social situation that feels welcoming. Green light. Your brain and body get prepared for a friendly conversation. But maybe the person in front of you feels threatening. Yellow light. You go into fight-or-flight mode. Your body instantly changes. Your ear, for example, adjusts to hear high and low frequencies — a scream or a growl — rather than midrange frequencies, human speech. Or maybe the threat feels like a matter of life and death. Red light. Your brain and body begin to shut down.
At first I misread that as calling for a friendly conversation between brain and body, but that's not the case, Brooks's brain and body don't have a very good relationship. Anyway, no. These things kind of work from the bottom up and the outside (sensory-muscular perception) in, on a natural selection basis, and there is no control center, only the thing that gives you the impression of one, once you've learned how to talk, in the linguistic system built around the "I" of your ongoing autobiography. That, which I got mostly from the great Gerald Edelman, you can have from me for free.

Where we actually are, of course, is not in the world of modeling cognition and behavior, but the world of therapy, as indicated in the name of Dr. Porges's discipline, which is not neuroscience by psychiatry (though he's a PhD, not MD, so he's not actually a psychiatrist either, by traditional standards)—cognitive behavior therapy (Brooks cites Lisa Feldman Barrett), dialectical behavior therapy, dance therapy, yoga therapy, and Prolonged Parent-Child Embrace therapy (Brooks cites the "nurture scientist" Martha G. Welch, who has an idea about autism designed to make parents feel guilty, as if they didn't have enough problems already).

Brooks, as usual, doesn't know that, though he's obviously responding to some comfort he found in reading, or looking at, this material, no doubt eased in by the soothing behavior of his heart and lungs which prevented him from fleeing or fighting. But the thing is, while therapies can work well on no proper scientific basis—think of acupuncture or chiropractic, or orthodox Freudian analysis—by the same token they don't say anything about the scientific basis, and the fact is this doesn't seem very well supported, according to Paul Grossman of the Universitätsspital Basel, who asked the users of ResearchGate if they knew of any evidence for Porges's key hypotheses:

After more than 12,300 views of my question, almost 5000 views on the associated project, and no positive replies (and several personal ones highly critical of the polyvagal conjectures), it seems that new or older positive evidence may not be available.  It appears increasingly unlikely that someone will come up with something to support the polyvagal suppositions....
If you mean that myths can affect people's lives, I have no problem with that. I also agree that is probably what has inflated the popularity of the polyvagal speculations. Wampold, in his work, makes a very convincing case that improvements in psychological wellbeing don't rely very much at all upon the method (or, perhaps, ritual would be a better word) chosen: improvement has more to do with having some ritual one believes in, a practitioner of it who seems competent to the client, a joint plan and goals, and maybe most importantly an atmosphere of trust and compassion.
However, my problem is that the ritual becomes conflated with science in this case, and the scientific aspect is used to sell the approach, when all the scientific evidence speaks against the speculations.
I don't feel quite that way about old Freud, but it's hard to care about what this theory says to David Brooks about the human condition, when it probably just isn't true.

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