Wednesday, November 26, 2014

Top-down causation and the emergence of agency

Top-down causation and the emergence of agency

A fabulous blogpost by Kevin Mitchell, in Wiring the Brain

Rarely does one see entire whole nervous system function, from peripheral to frontal lobes, explained in all its hierarchical glory, linked to reality and thermodynamics and evolutionary biology, all in one easy-to-read beautiful blogpost. Thank you Kevin Mitchell.
Not that there aren't quibbles. See the comment section.

The assemblage art of Bernard Pras is a good visual metaphor for how brains work, for watching how one's own brain works.

Bear in mind this happens with every sense, every kind of input, not just visual. Mostly there is a big moving pile of junk coming in all the time; the brain tries to figure out how to make sense of it, and succeeds enough of the time that life and events seem seamless and natural. Pretty cool trick when you think about it. It's had plenty of time to develop the ways of doing this, a good 500 million years. Ever since Devonian fish first invented spinal cords. 


Is the process intelligent? It certainly feels that way. Especially in us.

However, is it really? or is it just a well-honed, most-efficient way to transform physical energy within the constraints of the laws of thermodynamics?

I found another video yesterday that depicted a gob of some sort of goo ingesting a magnet, and immediately thought of macrophages in the body. They probably are about this intelligent. Life isn't necessarily required for this sort of behaviour. Just some sort of gradient.

"Nature abhors a gradient",  a quote by Dorion Sagan and Eric Schneider, from their book, Into the Cool: Energy Flow, Thermodynamics and Life, one of the best books I have ever read in my entire life.

Here is the goo video. 


On the other side of the neuroscience universe, people are building neurons these days in order to better study them. See Blanchard et al 2014, and this news story, Scientists convert human skin cells into sensory neurons.   Ignore the usual foible, nociception conflated with pain, while reading Pain and itch neurons grown in a dish, about Clifford Woolf's group, who just published Modeling pain in vitro using nociceptor neurons reprogrammed from fibroblasts


Let's never forget that as therapists, we input new sensation, new "junk" for our patient's brains to sort. We have to wait long enough for those brains we treat to sort through new junk.

The good news is, this process is completely automatic. 

Check out the video of Alan Watts, discussing how to not fight nature, instead, how to work with it.
Instead of rowing, which requires a lot of effort, just throw up a sail and wait.
The brain of your patient is the wind, and your contact with their physicality is the boat: let that person's brain move that boat itself.
Don't wear out your hands trying to row their boat for them. 


One last thing, a new paper on the insula, by Lucina Q. Uddin.
In the critter brain metaphor, insula is quite the chooser of which raw input to pay attention to and why. Very picky.
I like to think of it as a mid-level stage processor of raw data in, from every sense.

I try to make sure I'm not displeasing the insula of the brain of the patient at any stage along the way.

Not that it doesn't happen from time to time, despite my best efforts.
I live in a conservative small prairie city. Most people are religious, or at least go to church to see their friends, and quite a few think "evolution" is an idea from the vice category. I've lost a few people on that alone. The thing is, none of any of this information about how brains make sense of things, or might end up in pain, makes any sense without that key piece of reason in the story line.

Fortunately the bell curve here contains enough people who don't care one way or the other, that I continue to make a living, a reasonable living, no matter how science-based I choose to be. 

Yes, I chose the word "reasonable" deliberately, for both its meanings, in that sentence.


1. Joel W Blanchard, Kevin T Eade, Attila Szűcs, Valentina Lo Sardo, Rachel K Tsunemoto, Daniel Williams, Pietro Paolo Sanna, Kristin K Baldwin. Selective conversion of fibroblasts into peripheral sensory neurons.  Nature Neuroscience (2014)

2. Brian J Wainger, Elizabeth D Buttermore, Julia T Oliveira, Cassidy Mellin, Seungkyu Lee, Wardiya Afshar Saber, Amy J Wang, Justin K Ichida, Isaac M Chiu, Lee Barrett, Eric A Huebner, Canan Bilgin, Naomi Tsujimoto, Christian Brenneis, Kush Kapur, Lee L Rubin,Kevin Eggan, Clifford J Woolf. Modeling pain in vitro using nociceptor neurons reprogrammed from fibroblasts.  Nature Neuroscience (2014)

3. Lucina Q. Uddin Salience processing and insular cortical function and dysfunction Nature Reviews Neuroscience 19 November 2014
"The brain is constantly bombarded by stimuli, and the relative salience of these inputs determines which are more likely to capture attention. A brain system known as the 'salience network', with key nodes in the insular cortices, has a central role in the detection of behaviourally relevant stimuli and the coordination of neural resources. Emerging evidence suggests that atypical engagement of specific subdivisions of the insula within the salience network is a feature of many neuropsychiatric disorders."

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