Evolution of the neuron

I have just read, albeit slowly, Werner R. Loewenstein’s Physics in Mind: A Quantum View of the Brain. Having finished the book, I can attest I understand his argument even though my grasp of the physics involved is decidedly at the novice level. The last three chapters of the book were what drew me to reading it in the first place–those chapters cap the text with his model of how Evolution (he anthropomorphizes the theory) “chose to design”–in its exemplary, concise way–complex systems that led not just to life but to sentience.

Loewenstein compares neuro/biological processes with computers in terms of their being processors of information from the environments. He seems enthusiastic about computers in general, but he argues that artificial intelligence remains far away from evolving into sentience because consciousness requires many kinds of parallel processing that intersect and interact and filter out information. That complexity, he claims, will be difficult to engineer; yet over eons, the process of evolution accomplished it through a combination of physics, chemistry, and biology.braintrust-small

Loewenstein prioritizes the physics aspect: how electrical pulses in neurons parallel electrical pulses (attraction and repulsion) in atoms, how these behaviors can combine to create compounds or release energy; he uses analogies and spends several chapters on the eye, its neurons and dendrites and cones and rods, to demonstrate how a system of information reception and filtering can occur that relays information to the brain and then back to other information receptors and actors in the body of a worm, bird, or human being. Get enough relay systems going, and sight + touch + smell + hearing + taste evolve into the living animal. At some point, the multiple parallel information systems develop into consciousness (Loewenstein does not speculate where that point occurs–it is still “a mystery,” he admits).

~

Douglas Fox, writing in Aeon, quotes neuroscientist Leonid Moroz as saying, “There is more than one way to make a neuron, more than one way to make a brain.” In this fascinating article, Fox follows Moroz’s lengthy study of ctenophores, jellyfish-like creatures about which little is understood–though Moroz and his team of researchers are changing that. At the same time, their work suggests that our previous understanding of brain development is not necessarily the only model out there for how neurons and synapses can get information processed and acted upon to sustain a life. If that life is lived under very different environmental circumstances, maybe evolution might “choose” different paths of systematic information processing (ie, “thinking”).

…when he failed to find common neurotransmitters in ctenophore nerves back in 1995, it wasn’t simply that his tests weren’t working; rather, it was because the animal wasn’t using them in any way. This, says Moroz, was ‘a big surprise’.

‘We all use neurotransmitters,’ he says. ‘From jellyfish to worms, to molluscs, to humans, to sea urchins, you will see a very consistent set of signalling molecules.’ But, somehow, the ctenophore had evolved a nervous system in which these roles were filled by a different, as-yet unknown set of molecules.

Fox poses the researchers’ questions this way: “how divergent can nervous systems be? Do we truly understand how life senses its surroundings and behaves?” Science has generally, post-Darwin, followed a straight-line approach to evolution; but good scientists recognize that sometimes the road less traveled by has made all the difference.

 

Although the very idea of “sentient jellyfish” might appall many people, I wonder what sort of consciousness ctenophores would develop.  🙂

Advertisements

What I see

When I trek to New York City these days, I generally go for non-tourist reasons; my sister lives in Manhattan. It’s a day trip, and I don’t always avail myself of visits to big-city attractions–instead, I “hang out” with my sister and her family, which tends to mean home-cooked dinners in her apartment and walks around her neighborhood, greeting neighbors in the coffee shop or on the sidewalk. Often, that’s interesting enough, as she lives near Ft. Tryon Park and The Cloisters. On my most recent visit, however, we decided to take the A train south to tour the new Whitney Museum of American Art. It’s located at the base of the Highline Park, with views southward to the new World Trade Center and westward over the Hudson (making our evening visit gloriously pink-hued during summer sunset).

We spent a little over two hours at the museum, and our initial assessment was that both of us prefer the building itself as an architectural experience over the old Whitney building designed by Marcel Breuer. It isn’t all that much “prettier” from the outside; but the interior gallery set-up is more pleasant, light-filled, and navigable by patrons.

The opening show’s titled “America Is Hard to See,” a line culled from a slightly ironic Robert Frost poem (see an excerpt below). And the top floor gallery included a famous painting by e. e. cummings, so my poetry hopes were raised. The 8th floor of the museum was stunningly curated; I had high expectations for the rest of the galleries though, in the end, my reaction was decidedly mixed.

Thanks to Lederman copyright 2015. see whitney.org

Thanks to Lederman copyright 2015. See whitney.org

Levels 7 through 5 follow a chronological order, roughly, in terms of historical and cultural developments from the early 20th century to the present. This is a bit arbitrary, as artists alter their styles, and even their genres, over time–and some artists’ work spans decades, gaining and losing cultural momentum as fashions and criticism also change. As a result, there are clusters of pieces that cover similar themes but do not necessarily speak aesthetically to one another on the gallery walls. This was most obvious in the Viet Nam era gallery, which struck me as garish. The purpose in terms of education and theme was fine, but the aesthetics of the room as a display of art just did not convey, to me, what it might have in another perhaps less chronological arrangement.

Nonetheless, as far as getting visitors acquainted with American contemporary art, the new Whitney may be overall more successful than its predecessor. The former building’s galleries were arranged by donor collections and often had too much of the same, or else too little cohesion, and relied on the visitor’s being already reasonably familiar with contemporary art and art criticism. The exterior platforms of “outdoor galleries” (sculptural pieces) are impressive, though you may want to avoid the exterior stairways if you have a fear of heights.

I am happy to note that Calder’s Circus remains on display, along with the old and, by contemporary standards, poorly-produced video of Calder playing with these creations. I loved this piece as a kid and my own children also loved it.

~

Excerpt from “America Is Hard to See,” by Robert Frost

Had but Columbus known enough
He might have boldly made the bluff
That better than Da Gama’s gold
He had been given to behold
The race’s future trial place,
A fresh start for the human race.
He might have fooled them in Madrid.
I was deceived bywhat he did.
If I had had my way when young
I should have had Columbus sung
As a god who had given us
A more than Moses’ exodus.
But all he did was spread the room
Of our enacting out the doom
Of being in each other’s way,
And so put off the weary day
When we would have to put our mind
On how to crowd and still be kind.

The people on the streets and in the subways and in the neighborhoods were uniformly kind on this warm summer evening. Even when we got in one another’s way. That’s what I saw.

~