Introducing the brain:during sleep waves of fluid clean it (Introduction)

by David Turell , Monday, March 11, 2024, 22:40 (47 days ago) @ dhw

The brain: number of neurons

dhw: I found myself bewildered by what seemed like an obvious contradiction concerning the remarkable but unremarkable, exceptional but unexceptional number of neurons. I don’t want to subject you to a long read, as the problem is encapsulated in the two quotes below. I’m just wondering if you can explain the apparent anomaly.

DAVID: Brain size is not the key to mental ability. If so, elephants could out-think us.

dhw: That is clear. I just wanted clarification concerning the number of neurons. Here are the relevant, apparent contradictions:

QUOTES: Compared with other primates, the human brain is therefore not exceptional in its number of neurons, […] our superior cognitive abilities might be accounted for simply by the total number of neurons in our brain,which, based on the similar scaling of neuronal densities in rodents, elephants, and cetaceans, we predict to be the largest of any animal on Earth…

The human brain has just the number of neurons and nonneuronal cells that would be expected for a primate brain of its size, with the same distribution of neurons between its cerebral cortex and cerebellum as in other species,[…] and it may have been a change from a raw diet to a cooked diet that afforded us its remarkable number of neurons, possibly responsible for its remarkable cognitive abilities.

DAVID: The thoughts about cooking, calories and the brain are fully established. Our gut is different in small bowel size and colon size compared to apes. The 'garbaged' up discussion about our body size, our brain size and neuron number still comes down to our very unusual prefrontal area with five exact layers of pyramidal neurons like none other. Simply no other brain compares to ours. We are very unusual and these folks are simply trying to undo that approach. Our unusualness cannot be explained by natural evolution despite their attempt. Human exceptionalism grates on some folks.

dhw: The author acknowledges our “remarkable cognitive abilities”, but I can’t understand the apparent contradictions about the number of neurons. She says the number is not exceptional, but then she says the number may account for our superior cognitive abilities. Nothing to do with your false dichotomy of nature versus God. Maybe the apparent contradiction is simply a matter of muddled thinking, but I thought you might have been able to resolve it for me. We needn’t pursue the matter.

Let's not. Garbled thinking got past her editors.