Questions tagged [neuroscience]
The study of the structure and function of the nervous system and its components.
1,357
questions
111
votes
3
answers
26k
views
Are male and female brains physically different from birth?
Male and female brains are wired differently according to this article:
Maps of neural circuitry showed that on average women's brains were highly connected across the left and right hemispheres, ...
- 2,777
84
votes
3
answers
15k
views
Is there an RGB equivalent for smells?
Millions of colors in the visible spectrum can be generated by mixing red, green and blue - the RGB color system. Is there a basic set of smells that, when mixed, can yield all, or nearly all ...
- 935
75
votes
3
answers
16k
views
How does the brain's energy consumption depend on mental activity?
What is the impact of mental activity on the energy consumption of the human brain?
I am most interested in intellectually demanding tasks (e.g., chess matches, solving a puzzle, taking a difficult ...
- 1,947
63
votes
4
answers
9k
views
Are there organisms with fewer than 1000 neurons?
I'm developing neural networks comprised of just 3 to 10 layers of virtual neurons and I'm curious to know if there are any insect brains out there with fewer than a thousand neurons?
Are there any ...
- 1,871
62
votes
3
answers
11k
views
Why do smaller mammals move intermittently?
I was watching a nice little video on youtube but couldn't help but notice how snappy smaller animals such as rats and chipmunks move. By snappy I mean how the animal moves in almost discrete states ...
- 1,911
54
votes
5
answers
3k
views
Human perception of time depending on age
From what I can tell and what thus far all people with whom I discussed this subject confirmed is that time appears to "accelerate" as we age.
Digging a little, most explanations I found basically ...
- 893
52
votes
1
answer
7k
views
Do large animals experience a meaningful delay when moving their most distant appendages?
According to the Physics Factbook, nerve impulses travel at speeds anywhere from 1 meter per second up to around 100 meters per second. Blue whales reach up to around 30 meters long.
For a full-size ...
- 695
46
votes
2
answers
50k
views
Why can't we kill ourselves by holding our breath?
Is it possible to kill yourself by holding your breath?
This question is obviously copied from Quora, but I had heard it as a fact that we cannot kill ourselves by holding our breath and I'm looking ...
45
votes
3
answers
14k
views
Are humans more adapted to "light mode" or "dark mode"?
I was discussing with a colleague about using dark-mode vs. light mode and remembered an article arguing that humans vision is more adapted to light-mode rather than dark-mode:
I know that the trend “...
- 1,665
44
votes
2
answers
4k
views
Can brain cells move?
I was discussing this with my brother. I'm pretty sure I read somewhere that they can move.
Thanks
EDIT: By movement I mean long distance migration (preferably within the brain only).
- 641
43
votes
3
answers
80k
views
If the brain has no pain receptors, how come you can get a headache?
I've read many years ago in books, that the brain has no nerves on it, and if someone was touching your brain, you couldn't feel a thing.
Just two days before now, I had a very bad migraine, due to a ...
- 585
41
votes
2
answers
8k
views
What actually happens when my leg 'falls asleep'?
Most people have experienced the temporary loss of feeling and tingling in their leg resulting from sitting in an abnormal position for a short while. Usually you get a loss of feeling in your leg ...
- 3,703
36
votes
6
answers
43k
views
Why do the two hemispheres of the brain control the opposite sides of the body?
Why does the left hemisphere control the right and the right hemisphere control the left? I googled it but didn't find a good answer regarding this. Could someone explain?
Does this adaptation help ...
- 719
36
votes
2
answers
3k
views
Is C. elegans always observed with precisely 302 neurons? Are there ever individual viable exceptions?
This answer mentions that the C. elegans hermaphrodite has exactly 302 distinct neurons. This has made it a very effective model for a variety of types of biological research, including neurology and ...
- 5,094
34
votes
3
answers
4k
views
How and where, in the human brain, are memories stored?
Background
I am a computer programmer who is fascinated by artificial intelligence and artificial neural networks, and I am becoming more curious about how biological neural networks work.
Context &...
- 932
33
votes
1
answer
21k
views
What do you see when your eyes are closed?
If you are in pitch black and you close your eyes, you sometimes can see strange shapes of various colors. A lot of the time these shapes and colors change as you observe them. This phenomenon still ...
- 532
32
votes
4
answers
54k
views
How does cerebrospinal fluid circulate in the central nervous system?
Cerebrospinal fluid (CSF) is produced in the choroid plexus of the lateral ventricles and in the 4th ventricle of the brain. CSF then circulates through the ventricles of the brain and the ...
- 2,081
32
votes
4
answers
6k
views
Do men have more extreme variations than women?
This question was considered unsuitable for Skeptics and I think it is more suited to BIology than Cognitive Sciences
I was reading this article which I found interesting. It is not supported with ...
- 771
31
votes
3
answers
9k
views
Can humans ever directly see a few photons at a time? Can a human see a single photon?
I am not asking the following question: Can humans ever see a photon in the same way we see a chair?
My question is: Can a human retina respond to a single photon? If so, how does this happen and why ...
- 449
31
votes
3
answers
34k
views
Why is saltatory conduction in myelinated axons faster than continuous conduction in unmyelinated axons?
How does spacing apart sodium and potassium channels allow the action potential to travel faster down the axon? This is the reason always cited for saltatory conduction and myelination, but my mental ...
- 313
30
votes
3
answers
9k
views
Can one see flickering of a light bulb at 50 Hz?
Yesterday I had a BBQ with some friends. The sun had already set and the only light source left (besides some ambient light from the world around) was a low energy light bulb.
After a while I started ...
- 419
28
votes
5
answers
10k
views
What are the advantages of forgetting?
How forgetting things is helpful for the brain or the human body biologically? This web page
After some moment of being rude, selfish, or weak, either we are able to put it behind us, or the person ...
- 3,277
26
votes
7
answers
7k
views
Why can't we see in low light if staring long enough?
For me it seems reasonable that if I kept my gaze on a fixed point in a room with low light, a progressively brighter and better picture would appear before my eyes, just like a camera can see in the ...
- 379
26
votes
3
answers
19k
views
Do oysters feel pain?
Do oysters feel pain when you bite into the inside, or when you crack open the shell? I tried google searching it to no avail. When you bite inside the oyster or when you break the shell to open the ...
- 373
26
votes
2
answers
2k
views
What's the mechanism for being mentally tired?
I notice that after long tests, or long periods of critical thinking, my body and mind feel noticeably tired. Why does this happen? Are the neurons in my head not firing as quickly, or is there just a ...
- 323
25
votes
2
answers
38k
views
How do the brain and nerves create electrical pulses?
The information between the brain and peripheral nerves is sent via electrical pulses or signals, How then does a non-metallic human cell manage to conduct an electrical
signal?
- 527
25
votes
2
answers
2k
views
How is temperature sensed?
Can anyone summarize the mechanism by which when an object of a given temperature is placed in contact with, say, the skin on a human fingertip, the average speed of the particles of the object is ...
- 1,963
24
votes
9
answers
22k
views
Why have humans evolved much more quickly than other animals?
Humans have, in a relatively short amount of time, evolved from apes on the African plains to upright brainiacs with nukes, computers, and space travel.
Meanwhile, a lion is still a lion and a ...
- 932
23
votes
1
answer
451
views
What is the mechanism responsible for the periodicity of hiccups?
Hiccups (singultus) are caused by involuntary spasm of the intercostal muscles and diaphragm, producing a sudden inspiration with associated glottic closure. It seems the neurobiology of the reflex ...
- 3,149
22
votes
3
answers
1k
views
When did vision evolve for the first time?
Today I wondered what the first organism to evolve vision would have been. I assume that it would have been kind of primitive and basic, but of course extremely innovative and eventually useful to a ...
- 583
22
votes
3
answers
62k
views
Why can't neurons undergo cell division?
Many cells in the human body can divide and reproduce, making healing possible. Neurons, however, cannot reproduce, which makes diseases affecting the brain particularly crippling. Why can't neurons ...
- 1,405
22
votes
2
answers
2k
views
Does human brain store duplicate data?
There are several answers and articles about how the brain stores data, but none specifically cover whether a human's brain stores duplicate data.
I was reading in this article that a human brain can ...
- 705
22
votes
1
answer
766
views
Why does regular exercise increase brain volume?
It has been shown in several studies that regular aerobic exercise increases brain volume in aging humans. The changes were observed in hippocampus and were correlated with dramatic reduction of age-...
- 1,614
21
votes
1
answer
1k
views
Why do we feel tired if we sleep excessively?
When we eat, finally we feel full. I know which mechanism causes the sensation of being full. But when we sleep excessively we often still want more sleep. Why does this happen? Is there a mechanism ...
- 2,264
20
votes
1
answer
622
views
Why are fearful stimuli more powerful at night?
For example, horror movies appear to be scarier when viewed at night than during broad day light.
Does light have any role in this phenomenon?
Are there changes in hormones at night versus during ...
- 3,277
20
votes
2
answers
4k
views
What causes the range of severity of neurological deficits in Down's syndrome?
It's known that the severity of symptoms caused by a trisomy 21 varies from individual to individual. Part of the explanation for this range of severity is the finding that 94% of Down's syndrome ...
- 52.3k
19
votes
2
answers
4k
views
What makes learning more difficult as we age?
Why is it harder to adapt yourself to different cultures, places, and languages as you age? What makes breaking up with emotional patterns or ideas after years of habit more difficult?
Is there a ...
- 311
19
votes
2
answers
881
views
Can parts of a human brain be asleep independently of each other, or vary in the times required for them to fall asleep?
I know that some birds and marine animals can continue complicated activity (swimming, flying?) while one hemisphere of their brain is asleep.
I'm interested if human brain has some parts of it that ...
- 6,507
19
votes
1
answer
13k
views
Is it correct that the body only responds to the most painful stimulus?
I'm rather ashamed to say that this question is partly based on an episode of House.
I have previously heard that, if there are multiple simultaneous painful stimuli, the mind will only feel the ...
- 13.5k
19
votes
1
answer
3k
views
How does Sodium Valproate cause neural plasticity
I have been reading a fascinating paper: Valproate reopens critical-period learning of absolute pitch
18 individuals were given Sodium Valproate (VPA) for a fortnight during which they trained on a ...
- 461
18
votes
1
answer
549
views
The human brain in numbers I: neurons
Even though knowing the number of neurons in a functional unit or with the same function is not of main importance, it may be interesting to know their orders of magnitude, especially in the human ...
17
votes
3
answers
557
views
Under what conditions do dendritic spines form?
I'm looking for resources or any information about the formation of dendritic spines and synaptogenesis, especially in relation to how new connections are formed on a daily basis.
Does the ...
- 273
17
votes
2
answers
12k
views
Why do neurons have only one axon?
I have just learnt about neurons. I wonder why neurons have only one axon. Can they transmit nerve impulses faster and more rapidly when they have more axons? Does having more axons help in ...
- 719
17
votes
2
answers
343
views
What are the main mechanisms of interaction between the nervous and immune systems?
We know from pop science that our psychological states have an effect on our immune systems ("worrying ourselves sick", etc.), but what are the actual mechanisms through which our nervous systems pass ...
- 4,761
16
votes
2
answers
2k
views
Do humans learn to distinguish different senses?
Does a human being learn to differentiate between its senses at some stage in their development? Is there a time when it, for example, cannot tell if an input is a taste or a visual image?
The ...
- 283
16
votes
2
answers
3k
views
Do human beings have pheromone receptors?
What is the current consensus on whether or not humans have receptors that detect pheromones?
If there are purported receptors, in what anatomical areas are they located? With what organ systems do ...
- 4,761
16
votes
2
answers
811
views
How does an axon "know" it's not connecting to its own neuron?
I recently read about an experiment where they removed the dendrites and axons from rat neurons and placed them on a grid. After a while they started reconnecting and were able to learn things.
Since ...
- 163
16
votes
1
answer
3k
views
What limits the maximum spacing of Nodes of Ranvier and which organisms tend to have the widest gaps?
Assuming that a longer distance between gaps in the myelin sheath is beneficial for an organism due to the increased propagation speed, what is the limiting factor in determining the maximum spacing ...
- 13.5k
16
votes
3
answers
2k
views
Are two eyes necessary for 3D vision?
It has always been my understanding that humans have two eyes so that we can have 3D vision: the left eye sees more of the left side of an object than the right eye and vice versa. This helps us to ...
15
votes
6
answers
9k
views
Can the human brain be reduced to a binary system?
Does the brain really function like a computer as in, ultimately every response is related to a binary sequence based on whether particular neurons fire or not?
- 355