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9

Brains are not computers, and do not process information like computers. The trees from CS you are talking about are ways to run linear information stores through a central processing unit. Even with machines that can sort of do these operations in parallel, they are still very much series computations. Brains, on the other hand, are massively parallel, and ...


7

Short answer Neuroglia evolved after neurons did. The evolution of glial cells coincided with increased complexity of the organization of the nervous system. Background Glial cells are supportive cells for neural tissue. As such, evolution of glia before neurons would not be a parsimonious hypothesis, however not impossible. Glia indeed seems to have evolved ...


5

As a disclaimer, first please remember that brain size is only partially related to intelligence, and that whenever this comes up with regards to humans you should remember the long and ongoing history of badly-justified racism on the topic. So let's ignore intelligence, and just focus on brains and skulls. If a person has a bigger skull, then they have a ...


5

Short answer The structural anatomy of the cerebral cortex is closely related to its functionality. The cortex is a thin sheet of only a few cell layers deep. Expansion of processing power requires enlargement of the surface area of this sheet, and simply increasing its volume doesn't help. As a consequence, gyri and sulci developed during evolution to ...


4

The tiredness associated with depression/stress is not due to the 'brain power' increasing but due to a change in what parts of the brain are active and/or disrupted sleep. Anxiety can cause issues to the brain and body over time. Brain power is relatively constant For the average adult in resting state the brain consumes about 20% of the body's energy. It ...


4

Your question falls into an area of study known as allometry. It is generally believed that brain size must increase as body size increases1,2. This relationship has been demonstrated in fish 3,4, including carp. This phenomenon is also seen in other (non-mammalian) vertebrates including the Nile Crocodile (Crocodylus niloticus)5. This continued growth is ...


4

"Arc" is the Activity-regulated cytoskeleton-associated protein. It's one of the "immediate early genes", which are genes whose expression changes very quickly in response to certain neuronal activity. They are thought to be important in mediating the changes in expression of other proteins that accompany learning and memory in neurons. ...


3

In brief, so far as we can tell size matters far less than brain architecture. Consider that humans have only about half as many cortical neurons as a number of whales, yet are clearly far more intelligent. While we are still far from a complete understanding of the details of how intelligence actually works, neuron count is only part of the story. For ...


3

Short Answer Extracellular calcium ions’ “source” are probably cells called astrocytes that connect to both neurons and blood vessels. Calcium ions outside the pre-synaptic neuron are high in concentration, but since they are polar molecules they cannot passively diffuse in, where they are low in concentration, so they stay stuck outside the neuron. Voltage-...


2

These seem to be referred to in literature as "transcapsular" or "caudolenticular" (gray) bridges. My initial thought was that the picture you shared is just some weird artistic rendering but upon seeing histological slides these are quite prominent and familiar to me as part of the basic "look" of these structures in histology. ...


2

Not really. There really is little difference in neurons in mammal and indeed not much change across vertebrates. You have to go back all the way to jellyfish before you find major differences in neurons. https://pubmed.ncbi.nlm.nih.gov/30826503/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4159607/


2

I'd recommend reading a review paper on disorders of consciousness, which cover the spectrum of minimally conscious states, vegetative states, and coma. Brain death is outside the context of disorders of consciousness, but is often discussed for comparison. Nico Schiff is one expert in the area; I've attached a reference to a review he coauthored at the ...


1

I think that you can find a good answer to your question in a more careful evaluation of the hypothetical that you pose: since poodles are modified wolves, it should be easy for wolves to quickly evolve poodle brains in nature. How easy is it, actually, for a wolf to evolve into a poodle vs. evolving only the wolf's brain into a poodle's brain? The answer ...


1

Magnify your image. I just put it in GIMP and it is clear that there are several pixels in the red and the blue near the border which are a darker color than those adjacent - the drawing program must be responsible. Lateral geniculate nucleus That said, differences of red and green hue are handled more in the parvocellular layers of the LGN, while grayscale ...


1

As you mentioned yourself, there are differences in brain size, form and structure. This difference also affects the size and shape of cells, i.e. you won't find meter-long neurons in mice, but rather in bigger animals. However, the types of cells are overall the same among the mentioned species. It was found that the ratio of glia cells to neurons greatly ...


1

It's not a stupid question in my opinion. However, it is perhaps naive. Brain function is very complex and how the different parts of the brain exactly relate to memory and function is still being worked out. We can monitor neural activity outside the brain by a number of methods. The most common one you might have come across is an electroencephalogram (EEG)...


1

Color is a characteristic of visible electromagnetic spectrum, see the graph here. Electromagnetic means here that it has the same nature as radio-waves, X-rays, and gamma radiation, whereas visible refers to the region of spectrum - waves of frequencies ranging from TeraHertz to PetaHerz (i.e., from $10^{12}$ Hz to $10^{15}$ Hz). Specific colors essentially ...


1

The release of dopamine has a positive effect on the reward center in the nucleus accumbens. The neuron that releases the dopamine can be inhibited by other neurons, so there gets less dopamine released. The response elicited by a neurotransmitter, either excitatory or inhibitory, is determined by its receptor on the postsynaptic cell. ~https://www.ncbi.nlm....


1

Jung's premise is rather plausible: consciousness evolved rather than appeared suddenly, and therefore carries "pre-conscious" elements common to humans as a species. However, Jung goes very far in his interpretation of what may be hidden in subconscious, bordering on open mysticism - predicting accidents, wars, etc. I doubt there may be any ...


1

The other answers have done excellent job explaining how the stoned ape theory contradicts the Darwin's own theory of human origins. What remained unmentioned is that Darwinism have been the basis of the modern evolutionary theories for more than a century, and in this modern light there are even more glaring contradictions between the McKenna's theory and ...


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