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8

Biological neurons function in a very different way, as compared to the simplistic artificial neural networks of machine learning. For example, see how real neurons work and how they connect with each other. The types of neurons themselves are very varied: "...neurons to take specialized forms such as unipolar,bipolar, multipolar, anaxonic, ...


7

Some babies start walking by 12-15 months, so it's not exactly years before they can do it. They can also grasp things with their hands from birth. When first born they still don't have full ocular control, and especially can't focus except on strongly contrasting objects. If you watch a newborn, their eyes are often moving from place to place, even when 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 ...


5

The brain is trained to remember patterns and predictable associations. Randomness is the absence of patterns, so it's the exact opposite of what the human brain is for. A human can remember random numbers to about 67,890, which is the world record digits of Pi. That's about 20 pages of irrational numbers. Some people can remember 20 pages of word documents. ...


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

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

Evolution set us humans up to not regenerate our neurons on the whole, which is a pity since we can regenerate our liver cells, so it's not an impossible feat. If neurons die because you drank too much, banged your head, or just because they got old, they are gone. If this death is accelerated like in Alzheimer's disease, you can literally see holes in the ...


3

Single cells do not have brains. Plenty of multicellular organisms do not have brains either. Multicellular organisms such as fungi, plants, sponges do not even have nervous systems, and many organisms with nervous systems (like some jellyfish, molluscs, arthropods...) do not have something you could call a brain (I mean, I guess arthropods have a brain in ...


3

I can think of two factors that could explain why a civilization took so long to appear despite humans having fully developed their capabilities. Civilization is built into previous achievements: this generates an exponential growth in technologies making it easier to improve or create technologies giving that you already have the tools to create it. Think ...


3

It is confusing. The septum pellucidium is a thin membrane separating the left and right lateral ventricles. It contains white matter (nerve fibers), blood vessels and a few neurons. It has traditionally been thought of as just a separating membrane, but the fibers running through it connect to the hippocampus and hypothalamus and so it is probably a ...


3

"Intrinsic hypothalamic fibers" are fibers instrinsic to the hypothalamus; so yes, these are fibers either projecting from somewhere in the hypothalamus to somewhere else in the hypothalamus, or locally in the hypothalamus (the hypothalamus itself is a pretty complex structure containing many distinct nuclei). The paper you reference specifically ...


3

Unfortunately, it's really hard in the general sense. Even for FDA-approved drugs with well-characterized mechanisms of action, the binding profiles are incomplete. For GPCRs, it's you can run your compound(s) against a full panel of many GPCRs. For example, the PDSP (Roth Lab) can test for binding against multiple GPRCs using radioligand binding assays. See:...


2

Our brains usually make associations to different words including images, sounds, emotions, etc... which help reinforce the neurological patterns required to memorize sentences, etc... To remember something, it must also be repeatedly 're-thought' to strengthen the memory. Eventually with enough conscious and subconscious repetition of a thought, these ...


2

There is a lot of debate over what "thoughts" are in terms of consciousness, and this has been referred to as the "hard problem". However, it seems pretty clear that in some form patterns of brain activity are the "stuff" that underlies a thought/idea: if you change patterns of brain activity, you change the thought. Therefore, ...


2

Delta/theta/alpha/beta/gamma are not different states and so there are no changes "between" them. These are terms used to label different bands of the frequency spectrum. Every EEG has energy in all of these bands. Brain state can change/be measured by the relative changes in different bands (either relative to each other, or in absolute power ...


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

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

Walking is about more than having strong legs moving in a hinge motion. It's about coordinating all your leg muscles and your torso muscles. Babies have instincts which tell them how to coordinate all the muscle movements for suckling, but they still have to practice all the muscle movements for eating (and again, while learning to coordinate all the torso ...


1

Disclaimer: I'm not an expert, but my recent reading on this topic is fresh in memory, so I'm typing up something of an answer. The body does not remake any individual cells that die. In case of cells that regenerate, their place is simply occupied by cells which are newly born, or travel from elsewhere. Every individual cell is unique, with its own copy of ...


1

Yes, this is a very basic neuroscience question, something that would probably come up in the first week of a neurophysiology class or unit. The polarization of the membrane at rest is due to cells being primarily permeable to potassium at rest, and due to a concentration difference of potassium inside vs. outside the membrane. Inside, potassium is high, ...


1

Neuroregeneration capability is rather limited, and patients that go through the trauma that you speak of usually require life-long assistance[1]. One treatment that has come to light in the past two years uses stem cell delivery to the brain[2]. When a cell dies, if it is replaced, there are stem cells that do it (google mesenchymal or skin stem cells and ...


1

It's difficult to say a number because memory and activity are intermixed. Activity induces long-term modifications in the brain wiring which can be considered as memory, but at the same time, those connections play functional roles. For example, in the retina, the codification of the visual stimuli that are going to be transmitted to the brain is done by a ...


1

As has been commented, the answers to some of the questions here can be found in the literature. The nutrients and oxygen reach all tissues by the circulatory system — i.e. in the blood. And the link supplied by @trondhansen suggests a litre of oxygen a day. (I wouldn’t know — I never studied physiology.) However, as regards energy, I supply the following ...


1

Generally the axial length doesn't decrease: graph Although there is discussion of various conditions where it has been observed to decrease, i.e. nanophthalmos, microphthalmos, and retinoblastoma... A review of current research is here: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5501611/ quote: It is considered that the axial length reaches adult length ...


1

Not all hormones enter the blood - just as a quick addendum to the thorough reply above, and as per a comment above stating not all hormones from neuroendocrine cells go into circulation - seems to be true: many of the neuroendocrine cells release hormones directly into the organ where those cells appear - as per the gut, heart, lungs - here's a nice visual ...


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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