evolution of consciousness (Introduction)

by George Jelliss ⌂ @, St Leonards on Sea, Saturday, July 29, 2017, 17:19 (352 days ago)

Came across this and thought of you:

https://www.theatlantic.com/science/archive/2016/06/how-consciousness-evolved/485558/

All sounds quite plausible to me.

--
GPJ

evolution of consciousness

by David Turell @, Sunday, July 30, 2017, 02:02 (352 days ago) @ George Jelliss

George: Came across this and thought of you:

https://www.theatlantic.com/science/archive/2016/06/how-consciousness-evolved/485558/

All sounds quite plausible to me.

We all appreciate your thinking of us and providing this very well done explanation of the evolution of the human brain. I don't think he hasn't given us a good explanation of consciousness, but has afforded a good description as to how we arrived at the state of being conscious and responsive. Well worth reading.

evolution of consciousness

by dhw, Sunday, July 30, 2017, 11:03 (351 days ago) @ David Turell

George: Came across this and thought of you:

https://www.theatlantic.com/science/archive/2016/06/how-consciousness-evolved/485558/

All sounds quite plausible to me.

DAVID: We all appreciate your thinking of us and providing this very well done explanation of the evolution of the human brain. I don't think he hasn't given us a good explanation of consciousness, but has afforded a good description as to how we arrived at the state of being conscious and responsive. Well worth reading.

I add my delight at hearing from you again, George, and for a change I agree with David. Good history, but absolutely no explanation of consciousness. The essence of the whole thing seems to me to lie in this section. A talking crocodile might say:

I’ve got something intangible inside me. It’s not an eyeball or a head or an arm. It exists without substance. It’s my mental possession of things. It moves around from one set of items to another. When that mysterious process in me grasps hold of something, it allows me to understand, to remember, and to respond.”

The crocodile would be wrong, of course. Covert attention isn’t intangible. It has a physical basis, but that physical basis lies in the microscopic details of neurons, synapses, and signals. The brain has no need to know those details. The attention schema is therefore strategically vague. It depicts covert attention in a physically incoherent way, as a non-physical essence. And this, according to the theory, is the origin of consciousness. We say we have consciousness because deep in the brain, something quite primitive is computing that semi-magical self-description.

There is no theory of the origin of consciousness here. Merely the author’s contention that the crocodile is wrong, and it’s all due to neurons, synapses and signals, which is the standard materialist explanation. He may be right, but nobody in the world knows how it works or how it originated.

evolution: development of neurons

by David Turell @, Tuesday, February 20, 2018, 22:25 (146 days ago) @ dhw

They are such complex cells, did they evolve or were they designed:

https://darwins-god.blogspot.com/2018/02/this-didnt-evolve-few-mutations-at-time.html

"Nerve cells have a long tail which carries an electronic impulse. The tail can be several feet long and its signal might stimulate a muscle to action, control a gland, or report a sensation to the brain.

"Early researchers considered that perhaps the electronic impulse traveled along the nerve cell tail like electricity in a wire. But they soon realized that the signal in nerve cells is too weak to travel very far. The nerve cell would need to boost the signal along the way for it to travel along the tail.

"After years of research it was discovered that the signal is boosted by membrane proteins. First, there is a membrane protein that simultaneously pumps two potassium ions into the cell and three sodium ions out of the cell. This sets up a chemical gradient across the membrane. There is more potassium inside the cell than outside, and there is more sodium outside than inside. Also, there are more negatively charged ions inside the cell so there is a voltage drop (50-100 millivolt) across the membrane.

"In addition to the sodium-potassium pump, there are also sodium channels and potassium channels. These membrane proteins allow sodium and potassium, respectively, to pass through the membrane. They are normally closed, but when the decaying electronic impulse travels along the nerve cell tail, it causes the sodium channels to quickly open. Sodium ions outside the cell then come streaming into the cell down the electro-chemical gradient. As a result, the voltage drop is reversed and the decaying electronic impulse, which caused the sodium channels to open, is boosted as it continues on its way along the nerve cell tail.

"When the voltage goes from negative to positive inside the cell, the sodium channels slowly close and the potassium channels open. Hence the sodium channels are open only momentarily, and now with the potassium channels open, the potassium ions concentrated inside the cell come streaming out down their electro-chemical gradient. As a result the original voltage drop is reestablished.

"This process repeats itself as the electronic impulse travels along the tail of the nerve cell, until the impulse finally reaches the end of the nerve cell. Although we’ve left out many details, it should be obvious that the process depends on the intricate workings of the three membrane proteins. The sodium-potassium pump helps set up the electro-chemical gradient, the electronic impulse is strong enough to activate the sodium channel, and then the sodium and potassium channels open and close with precise timing.

"How, for example, are the channels designed to be ion-selective? Sodium is about 40% smaller than potassium so the sodium channel can exclude potassium if it is just big enough for sodium. Random mutations must have struck on an amino acid sequence that would fold up just right to provide the right channel size.

"The potassium channel, on the other hand is large enough for both potassium, and sodium, yet it is highly efficient. It somehow excludes sodium almost perfectly (the potassium to sodium ratio is about 10000), yet allows potassium to pass through almost as if there were nothing in the way."

"Nerve cells are constantly firing off in your body. They control your eyes as you read these words, and they send back the images you see on this page to your brain. They, along with chemical signals, control a multitude of processes in our bodies, and there is no scientific reason to think they gradually evolved, one mutation at time.

"Indeed, that idea contradicts everything we know from the science. And yet this is what evolutionists believe. Let me repeat that: evolutionists believe nerve cells and their action potential designs evolved one mutation at time. Indeed, evolutionists believe this is a proven fact, beyond all reasonable doubt."


Comment: Hunter then goes on to dissect an evolution-science paper about how neurons evolved and demonstrates how it is filled with wishful thinking., not fact A neuron appears in evolution from no predecessors and had to be designed to be this complex.

evolution of consciousness: a new comment

by David Turell @, Friday, May 04, 2018, 22:54 (73 days ago) @ dhw

A new book makes an attempt, looking at emergence, quantum theory and the amazing complexity of the brain:

https://www.wsj.com/articles/the-consciousness-instinct-review-how-our-minds-are-made-u...

"Mr. Gazzaniga’s approach echoes those of the American pragmatists of the late 19th and early 20th centuries, who believed that most philosophical problems needed not solving but dissolving. “Intellectual progress usually occurs through sheer abandonment of questions together with both of the alternatives they assume,” wrote John Dewey. Mr. Gazzaniga is not the first to suggest that the consciousness debate is hampered by just such a set of false alternatives: matter or mind, body or spirit. The dualist assumption that these are two mutually exclusive categories inevitably makes their reconciliation impossible, leading otherwise brilliant thinkers since Plato to abandon “their fierce reasoning skills and, deus ex machina,” throw in “a spook at the end of their analysis.”

"To escape the dualist trap, Mr. Gazzaniga takes as his unlikely inspiration Aristotle’s ancient distinction between four different kinds of causes. This review, for example, has a material cause (paper and ink), a formal cause (the shape of the letters on the page), an efficient cause (me writing it) and a final cause (to inform people about the book). Whether or not this taxonomy is entirely correct, it illustrates how “no one mode of explanation” suffices to understand anything, because the causal categories do not entail each other.”

"Mr. Gazzaniga updates this basic insight with the quantum-physical concept of complementarity, that “a single thing can have two kinds of description and reality.” We can think of matter as waves or particles, but not both at the same time. Similarly, the micro world of quantum physics follows different laws than the macro world of classical physics. “They inhabit different layers of description,” Mr. Gazzaniga writes, “and one is not reducible to the other.”

"The author’s point can also be made by thinking about the relationship between fundamental physics and biology. Both are hard sciences, but you simply cannot do the work of one with the other. Everything is made up of matter, but at different layers of organization different ways are needed to understand and describe it. This simple point cuts to the essence of Mr. Gazzaniga’s dissolution of the puzzle of consciousness. Once we accept that humans contain layers of physical organization, none of which can be wholly reduced to another, it is no longer puzzling that what goes on in the brain can have an objective, physical description and a subjective, mental one.

"Crucially, Mr. Gazzaniga also argues that it is wrong to attribute causal potency to only one layer—for instance, to suggest that neuronal firings can cause actions but decisions cannot. Heretical though this is to hard-nosed reductionists, Mr. Gazzaniga agrees with his mentor, Sperry, that “consciousness may have real operational value, that it is more than merely an overtone, a by-product, epiphenomenon, or a metaphysical parallel of the objective process.”

"Mr. Gazzaniga is very good at looking under the hood of consciousness to explain how its workings naturally follow from the ways in which the brain is organized. It is a hugely complex system with a layered, modular architecture, which enables it to “efficiently process multiple types of information concurrently.”

***

"Consciousness is not therefore a property of a central, single executive controller. What we perceive as consciousness is simply whichever module is most active, meaning that “its processing becomes the life experience, the ‘state’ of the individual at a particular moment in time.”

"Mr. Gazzaniga might be mistaken to nail his flag so firmly to the mast of the physicist-cum-theoretical biologist Howard Pattee. And he is almost certainly wrong in some details. But on all the main points, his instincts on consciousness are sound. Awareness is not the “special sauce” that brings dumb biological processes to subjective life but an emergent property of immensely complex neurological processes. This does not so much eliminate the mystery of consciousness as make it no more or less mysterious than the ultimately inexplicable existence of the universe itself."

Comment: This book is a materialist view which invokes the uncertainty of of quantum uncertainty and completely ignores the evidence from NDE's. But he certainly emphasizes the enormous complexity of the brain.

evolution of consciousness: another view

by David Turell @, Monday, May 14, 2018, 20:46 (63 days ago) @ David Turell

Another discussion of the problem of understanding consciousness:

https://theconversation.com/why-we-need-to-figure-out-a-theory-of-consciousness-93146

"there remains disagreement about whether or not we have a theory that actually explains what is special about the brain activity which produces our miraculous inner worlds.

"Recently, “Integrated Information Theory” has been gaining attention – and the backing of some eminent neuroscientists. It says that absolutely every physical object has some (even if extremely low) level of consciousness. Some backers of the theory claim to have a mathematical formula that can measure the consciousness of anything – even your iPhone.

"These big claims are controversial and are (unfortunately) undermining the great potential for progress that could come from following some of the ideas behind the theory.

"Integrated Information Theory starts from two basic observations about the nature of our conscious experiences as humans. First, that each experience we have is just one of a vast number of possible experiences we could have. Second, that multiple different components (colours, textures, foreground, background) are all experienced together, simultaneously.

"Given these two observations, the theory says that brain activity associated with consciousness must therefore be ever-changing, consist of lots of different patterns, and involve a great deal of communication between different brain regions.

"This is a really solid starting point for a theory, and to some extent, we have been able to test it. In one experiment, for example, researchers looked at brain responses to a short pulse of “transcranial magnetic stimulation”, in which a magnetic coil is placed on top of the scalp, and a very brief pulse of magnetic field emitted.

"The response was recorded from electrodes at locations all over the rest of the scalp. When fully awake, the response to the little burst of magnetic field would spread far and wide, in complex patterns of ripples.

"But when participants were in deep sleep, or under general anaesthesia, the response did not spread very far from the magnet, and the shapes of the ripples were much more simple. These results support the theory. They demonstrate that when we’re conscious, each region of the brain is doing something different, but are all managing to communicate.

"So far so good. But it would be great to go further than this. Hence the attempt to find a formula that can give us a precise “level of consciousness” from detailed data. It is here that the serious controversy begins.

"The theory claims that the ultimate formula will somehow quantify the information something contains. In this context, “information” means how much you can find out about the past and future of the object in question by looking in detail at the present.

"For example, you record voltages from a bunch of neurons in the brain, and see how well you can use one result to predict earlier and later results. If you can make good predictions from using the readings from all neurons, but only poor predictions if you use just some neurons, then you score high.

***

"Some people think perhaps this theoretical mathematical endeavour should be shelved for now. Experimental research on consciousness is going well, so maybe we should all just focus on that. But we can’t just do fact gathering experiments – we need a theory to understand what we’ve seen, and the basics of Integrated Information Theory do hold promise.

"What about the theory’s “panpsychist” position – the idea that everything is conscious? Can this be taken seriously? We need to be careful how to express this – talk of conscious spoons is unhelpful.

"If there were already many competing plausible mathematical descriptions of consciousness, none of which could be tested, then there would be no value in creating another. But so far there are zero, and only a handful of researchers have been working on this.

"Einstein’s theory of gravity was utterly compelling, even before it could be tested. Integrated Information Theory is not yet compelling to the informed mathematician. But it is by far the most promising foundation from which to tackle the very roots of consciousness.And progress on this ultimate frontier is worth some more conscious effort."

Comment: see the accompanying video:

https://youtu.be/Vl8J3K_ZLkg

It raises more questions than answers. An interesting point is made that the newborn brain is very inactive except for the amygdala, which is generally a fear center. It fits my view of starting as a blank slate with a suck and a grasp reflex as the only responses, as well as reacting to bowel and bladder needs.

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