Hot answers tagged

7

The evolutionary origin is alleged to be recent: Other animals do not have a preference for dissonance and consonance. (McDermott & Hauser, 2004). Humans have new auditory regions in the brain for predicting and processing speech, and processing the emotions conveyed in the voice. The human voice mostly has harmonics in the 3rd and 4th note due to the ...


6

Whenever you see a percentage, you should think "Percentage of what?". Not doing this is usually at the root of the trouble people get into with percentages. The water and fat percentages mentioned in the question are certainly not percentages of the same thing. The sources of the figures should make clear what the percentage is of, but non-scientific ...


5

I know we have sensors in the form of hairs that trigger a nervous impulse to the brain when they are stimulated. But as I understand it, each one can only send that on/off binary signal when they are triggered by a very specific level of sound. Your overall question borders on philosophy and the biology of consciousness which is hardly understood at ...


5

It seem's you are assuming that your / the adult human brain produces new neurons over time- this is (largely) incorrect: neurons are non-dividing cells and are all formed throughout embryogenesis and very early childhood / infancy (see also this question). Only very exceptions to this are known as adult neurogenesis (generation of new neurons), the most ...


4

Not much is known about the mechanisms involved, but they do appear to differ significantly from parasite to parasite. I'll discuss a few different examples here, and try to provide as much information as is currently known about how the parasites are doing it. There are likely to be many more different examples and mechanisms than these, and researchers ...


4

This review article [1] gives dopamine responses for rats (similar to the BBC article above) and includes references to the underlying studies: Sex/Food: 150% - 300% Alcohol/Ethanol: 190% (1g/kg) * Morphine: 200% (1mg/kg) * Nicotine: 220% (0.6mg/kg) * Cocaine: 350% (5mg/kg) Methamphetamine: 1000% (1mg/kg) These are percentages of the baseline ...


3

This is an interesting question with good comments. I did medical school, and I am here on unix.se, so let me give some thoughts: The central nervous system consists of "gray" and "white" matter. In the spinal chord you have this gray butterfly shape, in the neocortex it is "gray matter" (neuron's cell body) and "white matter" (neuron's myelinated axons). ...


3

First about the terms: The outer side of the cranial bones is covered by a single layer of periosteum that is specifically called pericranium. The inner side of the cranial bones is covered by dura mater that has 2 layers: the periosteal (or sometimes called endosteal) layer that is attached to the inner side of the bones the meningeal layer that covers ...


3

Some of the work of Bob Trivers makes some sense to me. He talks about parental investment https://en.wikipedia.org/wiki/Parental_investment. The "investment" of a man could be as little as paying for dinner, followed by a few minutes of sexual pleasure, and then he is free to go. The woman's investment for the same thing is the risk of pregnancy (or cryptic ...


3

During development of the brain neurons undergo several steps of differentiation. They transition from neuronal progenitors to mature neurons, resulting in different types of neurons, characterized most prominently by their primary neurotransmitter. During the differentiation, different genes are expressed, which in research is used to label specific cell ...


3

"Cortex" is a more general anatomical term for the outermost layer of a structure. It applies to both the cerebral and cerebellar cortex gray matter, as these are gray matter structures on the outsides of their respective parts of the brain. Nucleus is also a more general term; in the context of neuroanatomy, it refers to a cluster of cell bodies. Typically ...


3

There are two types of synapses namely Electrical synapse and Chemical synapse. In electrical synapse there is physical contact between two cells through gap junctions. In chemical synapse there is a small gap between two cells which is termed as synaptic cleft. The presynaptic and postsynaptic membranes at chemical synapses are separated by a synaptic ...


2

The components of the inter-stitial fluid will be dependent on where the synapse is though yes it will be aqueous. Good old fashioned diffusion over a concentration gradient will be responsible for ensuring sufficient neurotransmitter reaches the receptors on the other side of the synaptic cleft. Tough to find something you can easily reference online for ...


2

What gender someone identifies with or relates to comes in to play outside of utero as kids start to perceive themselves in a certain way. Biological factors, however, influence the likelihood someone will perceive themselves in a certain way. These factors may appear in utero or even later in life. Studies have suggested that developmental factors that ...


2

Here's an article I found that seems to attempt to address this question, using a kind of machine-learning approach involving "Long Short-Term Memory" (LSTM)-Recurrent Neural Networks (RNN), to classify EEG from participants who were watching either "easy" or "difficult" online lectures - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5620019/ . It's not a ...


2

Aside from autapses and pacemaking cells, there are also some kinds of sensory neurons that exhibit a spontaneous resting (constantly depolarizing) activity that helps with encoding stimuli. The benefit of having constant activity is that stimuli can further excite or inhibit this activity, and this can be valuable information. Sensory neurons such as ...


2

From the source you provided, the answers seem to be outlined well from the authors' sentence that states: The Pr [release probability] of SVs [synaptic vesicles] at the AZ [active zone] is set by a complex interplay of different presynaptic properties including the availability of release-ready SVs, the location of the SVs relative to the voltage-gated ...


2

By "cerebrum" I assume you really mean the cerebral neocortex, since the cerebrum includes other subcortical structures that themselves are quite distinct (e.g., the basal ganglia). Simply, the neocortex and cerebellum have completely different functions. The cerebellum performs a particular class of computations that are very different from the variety of ...


2

Not an answer, but a clarification. By "hippothalamus" (a probable typo) above it is probably meant "hippocampus", as is mentioned in wiki link. It is hippocampus which is known "to hold memories", but it is a part of a larger "memory" circuit and is a bit similar to temporary memory responsible for holding only recent memories and integrating recent ...


2

The minimal neural mechanisms that are jointly sufficient for consciousness (conscious percept, thought, memory, etc.) to occur, under constant background conditions, are called the neural correlates of consciousness (NCC) [1]. The background conditions are enabling factors that must be present for the NCC to be able to function (e.g., the heart must beat ...


2

Part of this question is due to the function of microglia in the healthy brain (as we currently understand it). The general idea is that microglia in a healthy brain are in "surveillance mode," and have long, thin processes that extend of the cell body to monitor the environment. It would be like beat cops splitting up and walking the streets when no crime ...


1

The hippocampus is considered archicortex rather than neocortex. Sometimes hippocampus is considered "sub-cortical" but I think this is only really fair if you really mean "sub-neocortical"; it's common for "cortical" to be used as a shorthand for neocortex in human neurobiology. Writers will be more specific when necessary. The piriform cortex and related ...


1

When you just want to list the components of the brain, that is to say what the brain consists of from the gross anatomy perspective, you can say that the main parts of the brain are: cerebrum cerebellum brainstem You can also say that the parts of the brain are some smaller, but anatomically well defined components, such as the pineal gland and pituitary ...


1

Great questions! Here's some quick answers, but I'll give an additional little recommendation at the end if you're interested: How much of an effect does this destruction of neurons have on movement? Answer: A large effect. The key term here is "Parkinsonism," meaning that the symptoms resemble Parkinson's disease. This often involves motor symptoms ...


1

(This is such a difficult question to begin answering in any satisfactory manner, though I think can be addressed for pedagogical purposes in line with the aims of this SE.) Before we address the question, I think it is prudent to think about the difference between stimulation and activity. A neuron can be self-activating without external stimulation, or ...


1

Another example is the paired helical filament of Alzheimer's disease, so-called because neurofibrillary tangles have a ribbon-like structure when viewed under the electron microsocope. It is now accepted that paired helical filaments consist of a single protein, microtubule-associated protein tau, in a polymerized and hyper-phosphorylated state. (see Lee ...


1

not sure if you are still looking, but I have two recommendations for you. "Limbic systems for emotion and for memory, but no single limbic system" is a really long, but really great article on the topic. You can find that online here: https://www.sciencedirect.com/science/article/pii/S0010945213003110?via%3Dihub It's been a while since I've read this ...


1

I'll attempt an answer, but please know you don't have a clear nor defining question to address. This is more suited for conversation or open discussion, and I recommend starting a chat on the topic. Please be wary the question may be put on hold. I'll give it a go and respond from the top down. I absolutely don't think this is going to be fruitful for other ...


1

In any comparison of intelligence, the most important question is how are we going to define intelligence? The typical inclination is: intelligence is what is required to do the things that we admire as difficult intellectual feats. More generally, intelligence is what it takes to do things that humans do. Making comparisons between species is inherently ...


Only top voted, non community-wiki answers of a minimum length are eligible