Brain complexity: learning new tasks (Introduction)

by David Turell , Wednesday, December 13, 2017, 01:01 (2538 days ago) @ dhw

DAVID: I maintain that only a larger more complex brain (pre-frontal cortex) can conceive of more complex concepts.
dhw: So you maintain that only the “soul” can conceive concepts, but only the brain can conceive more complex concepts…
DAVID: The soul conceives new concepts by using a more complex brain cortex. For example, in teenagers they cannot fully evaluate dangerous situations and other considerations until the prefrontal areas are fully developed at age 26+/-.

dhw: As usual, the word “using” covers a multitude of activities, but it does not cover “conceiving concepts” if you insist that only the soul can conceive concepts. And I doubt if any of us can “fully evaluate” anything! The brain provides information, which it continues to do throughout life, and if the soul exists, it learns from experience (just like immune cells), and in turn uses the brain to implement its concepts.

This seems reasonable if you accept that consciousness/soul run the brain.

> dhw: As the child's brain develops, it acquires and passes on more information and can implement more concepts provided by the soul, which is fed by the never-ending flow of information. But if only a more complex cortex can provide the evaluation, and hence all the concepts and decisions relating to the information (as in your first statement), you can hardly avoid the conclusion that thought stems from the brain. It may well do so. (Materialism versus dualism.)

And my point is the soul/consciousness runs the brail to create thought.

DAVID: I can accept this much of your theory. But our highly complex brain is not a pre-sapiens brain and with its high complexity may well have developed a method of much enhanced complexity to allow the shrinkage. Pre-sapiens present a different issue, lack of enhanced complexity, and therefore a different requirement for enlargement.

dhw: Why do you say “but”? You are repeating my own hypothesis in different words. Yes, our brain is different because instead of expanding, it complexifies. And yes, increased efficiency of complexification may have resulted in shrinkage. And yes, complexification could not cope with pre-sapiens’ demands, and so the brain had to expand.

What demands in a survival type life? Minimal compared to what our brain does now. I don't see the explosion pressures you are looking for.

An excellent summary of the history, and so I don’t understand why you find the process so mysterious. The brain reached its optimum size 300,000 years ago. For 290,000 years humans lived just as some of the remote tribes live now. Why not? Those tribes have managed perfectly well, and would no doubt go on doing so if we western know-alls didn’t keep interfering. But 10,000 or so years ago certain individuals came up with new ideas, and these were capable of rapid development. The optimum-sized brain was not waiting around to be used - it was INADEQUATE!

Not inadequate, but enlarged with many more neurons and branching axons and synapses. Then it could easily the exploding knowledge and thought over the past 10,000 years.

dhw: And so the new uses demanded a new technique for coping: namely, enhanced complexification instead of the no longer possible expansion.

I believe it was highly complex to begin with, waiting for us to use it, but we had to learn to use it.

dhw: The driving concept would have been the same mixture of survival and improvement (which you have acknowledged as a “major tenet”) that has driven all of evolution. Why did it take so long? All of a sudden 290,000 years is a long time. According to you it took your God about 3 million years to work our way from a lumbar change to full bipedalism. Homo erectus lived for at least a million years without making a great deal of progress. Why do you think your God left him hanging around all that time before doing the brain expansion trick?

I don't know why each jump in size took so long. Ask God. We have to accept what we see.