Questions tagged [neuroscience]

The study of the structure and function of the nervous system and its components.

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Are there neurons that can sense light shining in your ears?

I know someone who bought earphones that shine light in you ears. According to what he was told, there are neurons that sense light and then make you feel wide awake when activated, which seemed like ...
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What causes REM atonia to be lost in sleepwalking?

I understand that in normal REM sleep the voluntary muscles are in effect paralysed in order to prevent an individual acting out their dreams. This paper indicates that there are likley to be ...
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Effect of pupil responses on the electroretinogram

The electroretinogram (ERG) is a measure of electrical activity of the retina. It is typically recorded from the cornea with a wire electrode or gold-foil electrode. Generally, the the ERG is ...
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Is it possible to feel pain in some part of a body, but the pain “feeling” is introduced somewhere else?

Is it possible to feel pain in some part of a body, but that the cause of the pain is situated elsewhere in the body? For example, somebody feels pain in his toe, but it turns out that this pain is ...
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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?
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How does a brain distinguish stimuli?

If all the brain ever "sees" is action potentials, how do we know that one set of action potentials denotes a flash of light, another one signifies a loud sound, etc ?
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How can action potentials be generated through thoughts?

I think I understand how a signal is transferred from neuron to neuron (from How do the brain and nerves create electrical pulses?). My question, however, is not about the standard textbook material ...
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How do neurons find each other?

Neurons form complicated networks in brains, but their connections can't be random (at least not entirely). Brains function similarly among all members of individual species, and that functionality is ...
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How does a neuron change as you learn?

I am currently taking a course called "Introduction to Machine Learning with ENCOG 3", and I have a question about how well the Artificial Intelligence (AI) algorithm for a "neural network" ...
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What portions of the brain have drastic changes in activation when we “sense” someone is there?

I was watching an old Arnold Schwarzenegger movie ("Commando") where he plays an elite soldier (surprise). An enemy tries to sneak up on him, and Arnold says that he smelled the other guy approaching....
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Why does getting certain chemicals in cuts hurt?

More specifically, shampoo. What are the mechanics of detecting a noxious chemical stimulus in terms of which receptors recognise what, how do they do it, and how is this information relayed to the ...
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Why do antidepressants have a delayed onset of action?

Why do antidepressants take so long to reach efficacy? I've read of theories about it perhaps being due to the strength of negative feedback via serotonergic and adrenergic autoreceptors during the ...
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Why do neurons die so quickly (relative to other cells) when deprived of oxygen?

This question could be considered a follow-up question to Why is a lack of oxygen fatal to cells?, although the top answer there does not address why damage starts to pop in. The answer says this: ...
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Long-term-potentiation and memory. Where do we stand?

I was reading the answers to the question: How and where, in the human brain, are memories stored? and, as expected, LTP and LTD came out. Every time I read about LTP/LTD there is always something ...
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What is Peter's rule in neuroscience?

I have heard and read about Peter's rule informally in the past, but never saw a formal definition or description. Informally I have learned to understand Peter's rule as the assumed correlation ...
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How does Golgi's neural histological stain work?

What is known about the targets of Golgi staining of neurons? Are larger neurons more likely to be stained? Are specific cell types more susceptible than others? The current wikipedia article says ...
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Why does this illusion work?

This is another image I found on Google+ All lines are absolutely straight, parallel and perpendicular but why does it appear to have a curvature? Related: How does this illusion work?
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Systems identification in small neural network

When analyzing data from cortex, we often try to understand what each neuron does in terms of its inputs from other neurons - a specific kind of a systems identification strategy. Most current ...
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Is it possible for any animals today to have more than one brain?

Is it possible for any organisms in the animal kingdom to have more than one brain?
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Could an “overactive” brain increase the chances of Alzheimer's Disease?

From Raichle ME. 2010. Two views of brain function. Trends in cognitive sciences 14: 180–90: Alzheimer’s disease (AD) is the most common cause of progressive cognitive decline and dementia in ...
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How old does a baby have to be before it can retain memories?

For most people (my earliest memories are of perhaps when I was 2 or so) their earliest memories would be when they were over a year old. How old does the average baby have to be before it can ...
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Which part of the brain needs to be shut down to lose conciousness?

Whether it is mechanical (trauma), chemical (anaesthesia) or electrical - which part of the brain is shut down to cause loss of consciousness?
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Is the minicolumn the unit of the neocortex?

There are many arguments for what the unit of the neocortex is. "Columns" seem to be the standard, but what exactly those are is extremely contradictory between individuals, cortical regions, and ...
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Why do we like music?

Music is, of course, just a sequence of sounds. Sounds are vibrations in the air, which our ears detect. So why do we find certain sequences of sounds to be appealing? What makes us want to hear these ...
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Do snakes get dizzy?

I've seen snakes get captured in sacks and I've wondered if the snake would get dizzy if the sack were twirled around. I have not done any tests (and don't plan to) because snakes scare me.
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Does a neuron ever generate an action potential without stimuli?

Most accounts I read involving action potentials and synapses and the like tend to focus mostly on the action potential as a mere automatic reaction to another similar event happening upstream. From ...
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What happens once a brain is full?

I just read the answer to this question, and it got me thinking... If the human brain (or any other brain) has a finite amount of storage, what would happen once the brain has taken in its maximum ...
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What kind of memory is “keyboard/keypad memory”?

I work in IT and I have observed many people who cannot remember their iPhone passwords or computer passwords off the top of their head. However, if presented with a keyboard or a phone with a ...
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Are brain cells replaced over time?

You know how your cells die all the time and new ones are made to replace them, so you practically have a new body every maybe 5 years? Many people say you become a completely different person every ...
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What are the advantages and disadvantages of being ambidextrous?

Most of us have one dominant hand. We find it nigh on impossible to do very delicate or dextrous activities with our other-hand. This seems like an apparent weakness, and a rather odd one when you ...
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How do neurons form new connections in brain plasticity?

I've been reading about brain plasticity and how the brain can "rewire" itself. One of the things that is not clear to me - how neurons can establish new connections. Does this rewiring mean that ...
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Is it possible for a human to wake up in a wrong way?

There's an old folk saying that goes like "He got out of bed on a wrong foot" - to indicate that the person's day is going poorly because of the way that person woke up. Is it is possible for a human ...
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What are the “stars” we see after a bump on the head?

Sorry if this might appear funny. When I close my eyes for a longer time, and suddenly open it, I see some twinkling white small circles, and when i concentrate on anyone of them it disappears, as ...
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Can we change our dopamine baseline levels?

Can we change our dopamine baseline levels? High dopamine levels improve alertness, problem solving, but may also cause anxiety and aggression. I've read that smiling and laughing, eating certain ...
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Why do cyanide and arsenic smell like almonds and garlic, respectively?

Why do humans smell arsenic as garlic or cyanide as almonds? Do both smells activate the same receptor? Is there any reason why our brain interprets these smells the same?
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Do taller people have larger somatosensory cortices than short people?

When we assume that peripheral touch receptor densities are equal in tall and short people, then tall people should have more touch receptors than short people, given the larger amount of skin surface ...
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What would be the conduction speed of A-alpha fibers, were they unmyelinated?

It's known (Hursh 1939) that myelinated axons exhibit the behavior $v = 6d$, where $v$ is the propagation speed [m/s] and $d$ is the axon diameter [μm]. A related relation for unmyelinated axons is (...
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Which brain regions are D1 dopamine receptors expressed, and which brain regions are D2 dopamine receptors expressed?

This is a follow-up question to If D1 receptors stimulate adenylate cyclase (through GPCRs) and D2 receptors inhibit it, then why do mutations in both have similar effects?. As a further question - I'...
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Understanding the brain: how are neurotransmitters released in the brain?

I have a basic knowledge of how neural networks work. A potential difference is created that forces sodium, potassium, chloride, and calcium ions to flow which carries an electrical signal to the end ...
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How fast do we fall asleep?

When looking at the process of sleeping, most research I find point to a group of mutually inhibitory cells which form a sort of biological "flip flop." There's cells that promote awakenness and ...
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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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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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How are neurons / synapses “biased”?

I'm trying to see if I understand this correctly. I've read the question Can the human brain be reduced to a binary system? and one of the answers explains: While action potentials are usually ...
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Why are potassium channels slower than sodium channels?

I am relatively new in the subject of biology. I have a strong mathematical background and in order to get into the field of computational neuroscience, I am trying to get some biological background. ...
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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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At what point during an action potential are the sodium potassium pumps working?

I'm trying to understand how all of the potentials during an action potential are created. My question specifically is about the sodium potassium pumps, however I would also be grateful if someone ...
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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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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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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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