Questions tagged [neuroscience]
The study of the structure and function of the nervous system and its components.
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Do memories have mass?
If it were possible to live forever, would our brains grow infinitely with the number of memories that we store? Or would we remove old memories as we create new ones?
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Why do some people become more aggressive when tired?
Why do some people become more aggressive when they are tired? I've been thinking about this question for a few days and my 'hypothesis' is that the neural activity in the prefrontal cortex lessens as ...
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What is the mechanism behind tinnitus?
I seem to have come across two contrasting explanations for tinnitus induced by loud noises- i.e. damage to the hair cells in the cochlea.
On the one hand, I have read that damage to the hair cells ...
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Why do neurons die so fast without oxygen and nutrients?
Some human tissue can survive without oxygen a couple of minutes, even hours.
Why are the neurons are so "weak" and depends so much on oxygen and other nutrients and cannot live without them for ...
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How does the brain avoid feedback loops?
The article Ants Swarm Like Brains Think really helped me to understand the way that neurons which are pretty dumb on their own (like ants) can work together to create a pretty genius system (a brain ...
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Why can action potentials not be initiated at dendrites?
Why are action potentials not initiated at dendrites, although dendrites are the first to receive input from the presynaptic cell?
In fact, excitatory postsynaptic potentials (EPSPs) at the dendrites ...
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What is a inhibitory tone when talking about neurons?
In this SE answer: Could an "overactive" brain increase the chances of Alzheimer's Disease?
user @nico used the word inhibitory tone What does that ...
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How is membrane capacitance related to the increased speed of saltatory conduction?
Here is the original question which inspired my question. As explained by the answers there, the reason saltatory conduction in myelinated neurons is faster than non-myelinated conduction is because ...
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Are there any types of cancer that cause neurons to divide?
After birth neurons generally do not divide. But is there any specific type of rare cancer or tumour where neurons divide? And if there is such a cancer, then how is it possible for a neuron to regain ...
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Why does it hurt more when you touch a nerve directly?
I am not a biologist nor know much about biology (so please explain in layman's terms) however I have always been curious as to why this is.
What causes the difference in pain between touching an ...
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What were the first neural systems like?
I'm curious about the origin of the neural network.
I'm thinking perhaps once life evolved beyond the single cell organism, it needed a simple neural network to coordinate those cells, and cell ...
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Refractory period in action potential
I know that the part E in this graph is definitely the part of refractory period.
My question : Will there be any effect on B,C or D if a stimulus is given at time B,CorD respectively ?
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Is there a biophysical causation from local field potential (LFP) to spikes?
Many experiments showed that neurons tend to fire at some phase (usually trough) of local field potential (LFP) oscillations, such as theta or gamma rhythm. LFP is supposedly generated by a population ...
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How reversible is DAT upregulation from long-term ADHD medication use?
A mechanism for ADHD stimulant medication tolerance has now been found. See http://neurosciencenews.com/adhd-medication-patient-brains-adapt-dat/.
Here's the thing though: what exactly is the "signal"...
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Why do neurones use chemical signalling at synaptic junctions?
When a neurone fires, it sends an electrical signal that jumps down the axon via the nodes of Ranvier very rapidly. At a synaptic junction, chemical Brownian diffusion signalling with receptor surface ...
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Why has evolution made neurons use spiking?
I'm going to be forward and say that I'm not a biologist. I don't claim to fully understand the functionality of a neuron from an electrical/chemical perspective... I'm curiously gazing from the ...
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Why do humans alone have the capability to have religious/spiritual experiences?
What is it in our brain that makes having such experiences possible? I assume other species don't have these. Sure there are instances in the natural world where you can see individuals of the species ...
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Is lumosity.com based on science?
I always see these Lumosity ads on TV, and I personally feel they are just trying to "sell me something". I did some layman's research (wikipedia) and read that "Studies of Lumosity's effectiveness ...
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Why doesn't local anesthesia affect muscles?
While having a dental surgery, I've got this question that why I can still talk, open/close my mouth, move my lips and so on while I can't feel anything at all in my mouth?
If the local anesthesia ...
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Are sensory receptors neurons?
Background
There are many receptor types in the body, with various functions and various mechanisms of transduction. Receptor cells are considered to be part of the peripheral nervous system, as they ...
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Are unilaterally deaf people able to determine where sound comes from?
My question is on people deafened in one ear, but normal hearing in the other.
Time and level differences between the two ears are only part of how the human body can localize the source of the sound....
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Do ants feel pain?
I have watched video on youtube where guy pours molten aluminium into fire ant colony to make casing. In the comments below there's huge discussion on is that a right thing to do. I am on the side ...
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The concept of backpropagation in neural networks actually occurs in the brain?
I am aware the Human brain has many functionally distinct components, but let us specifically consider the Human visual cortex: could Artificial Neural Networks (ANNs) be "trained" (through, e.g. ...
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Is there any way a human could whistle and be unable to speak?
Is there any situation anatomically, where a human could understand the speech of others perfectly, without any capabilities of speech themselves, but would retain the ability to whistle with a tune?
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Single long axon vs serial neurons
Based on the comments in this post and also this chat. For discussions and speculations please comment in the chat.
The basic question is what is the advantage of having a single long axon such as ...
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How harmful is aluminium?
I have been taught in school that aluminium is harmful for brain.
Thus sour meals should not be cooked in aluminium pots and it is unhealthy to add lemon juice to tea while there is teabag in the cup, ...
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Why is the human ear most sensitive to 4000 Hz tones?
Human hearing sensitivity is dependent on frequency, which can be visualized by equal-loudness (iso-loudness) contour plots. An example is given below (Taken from here).
This plot shows that a tone ...
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What is the latency between paired neuronal responses in the brain?
Is there any data on how long it takes for signals to propagate from one neuron to its neighbors in complex networks, such as the brain (particularly the neo-cortex)?
If not, is there any reasonable ...
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What's the worst that can happen from too much sleep deprivation? Can you die?
It is well known that sleep deprivation causes considerable discomfort in humans (and has even used as a form of torture), but nevertheless there have been people who went through protracted sleep ...
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What is the function of nodes of Ranvier in axons?
In a neuroscience class I'm taking, it was explained that myelin covers axons in sections, the uncovered sections are called nodes of Ranvier, and signals propagate much faster in the covered sections....
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Is there a biological basis to physical attraction?
Is there something encoded within us that makes us attracted to, e.g., someone
taller or shorter
with blonde or brunette hair
with green or blue eyes?
Or, is this phenomenon completely based on ...
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Are Schwann cells the sole source of myelination in PNS?
Are Schwann cells the only source of myelin for axons in the peripheral nervous system, or are there other neuroglia or other processes that result in myelination of PNS axons?
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Can people with paralyzed eye muscles see?
As far as I am aware, the saccades of the eye are central to visual perception. If the eye is held still, the human stops seeing, even if light is reaching the retina and the visual pathway is intact. ...
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How long does a signal from the brain take to reach the limbs?
If the brain sends a signal to move what's the time it takes the signal to travel via neurons to motor neurons in hands, arms and legs?
How fast do those signals travel?
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Is the squid giant axon the fastest conducting unmyelinated axon known?
The conduction velocity of the squid giant axon can reach 30 m/s. Is there any known example of an even faster conducting unmyelinated axons?
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Is the six-layer cortex model of the mammalian cortex still the most accepted model?
I've been reading a bit about the different layers of the cerebral cortex and its clear that certainly not every region of the cortex has the same number of layers. Thus, the idea that every region ...
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What is the limit of time resolution in fMRI?
I was reading about a few studies on estimating functional connectivity between brain areas using fMRI signals. However, as far as I know that fMRI has a very poor time resolution, roughly in the ...
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Can we disambiguate competing molecular mechanisms of learning and plasticity by measuring electrical activity of neurons?
I have been reading with fascination about the several molecular- and cellular-scale mechanisms and structural changes that underlie what we refer to as long-term plasticity. For instance, [1], [2], [...
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How do our eyes detect light at different frequencies?
Here is my confusion: we can see colored light of different wavelengths: form red to violet. To my understanding, these stimuli cause a confirmational change in the photoreceptors in our eyes and ...
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What keeps the resting potential of neurons constant at -70 mV?
I know the sodium-potassium pump pumps out 3 Na+ ions and pumps in 2 K+ ions per reaction so the negative charge in the axon increases. However, once the voltage (difference of charge inside and ...
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What causes Paresthesia (Pins and Needles) at a cellular level?
I've looked it up in plenty of places like the Wikipedia page and such, and it is clear that the most common cause of Paresthesia is either a fair amount of pressure on a specific patch of skin ...
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What part of the brain controls depth perception?
Specifically the part of the brain that does depth perception based on binocular vision. I have searched all over the web and have turned up nothing. Is it the same part of the brain that processes ...
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If tinnitus is, in many cases, caused by damaged ear hair cells, couldn't it be solved by a mini cochlear implant that sends a constant signal?
If my understanding is correct, tinnitus is in most cases caused by damage to the inner ear hair cells, especially on the basal parts of the cochlea, which correspond to high frequencies. So, for ...
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Is brain transplantation possible?
Many organs can be transplanted nowadays, including the liver, lungs and kidneys.
Can the brain be transplanted?
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Is the ratio Brain Mass/Total Mass still considered a valid indicator of intelligence?
I was reading this(1) and it led me back to ask a very basic question (I'm not a neuroscientist). All the way back to undergrad anthropology and neuroscience courses I remember being taught the ...
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Neuronal Architecture of the Brain
To what extent do brains (e.g. of humans) contain recurrent connections?
I am studying artificial neuronal networks and frequently encountered the statement, that recurrent neural networks are ...
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How does a pinched nerve cause pain (at the molecular level)?
Is this due to pressure differentials in the surrounding tissue? (Is it possible to have a pinched nerve without compression of the surrounding tissues, and does this cause pain?)
What are the ...
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How precisely can we sense temperature differences?
We have thermoreceptors, thus we can sense temperature (both warm and cold). I'm interested in the sensitivity of our thermoreceptors - What is the smallest temperature difference that we can sense? ...
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Advantage of opponent color?
Opponent process is a color theory that states that the human visual system interprets information about color by processing signals from cones and rods in an antagonistic manner (source).
What is ...
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Is it technically possible to make someone see something when their eyes are closed?
I'm writing a little article and need any information about how human vision works and latest
technologies and discoveries around. Actually its not a professional article. Its for a group of my ...