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

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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 ...
1
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0answers
34 views

What happens to the human brain when unconscious?

What part of the brain gets affected and does it harm the brain? Thank you I just needed some extra info for a video I'm making.
0
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0answers
15 views

What information do bipolar cells encode?

Short version: I don't see what information on-centre bipolar cells are actually capturing. Longer: Actually, the question could be extended to on-centre retinal cells as well, but I'll focus on ...
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1answer
16 views

Voltage sensitive dyes technique: What is the underlying measure?

I just discovered voltage sensitive dyes technique: first of all what imaging techniques do we use? And I have seen that figures are labeled with ΔF/F0, what does it stands for?
8
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1answer
598 views

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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0answers
5 views

If I think of a checkerboard, is there a similar structure to see in my visual cortex? [migrated]

When I´m imagining a checkerboard in my mind, can one find, with all kinds of fancy equipment, a corresponding figure in the area of my visual cortex? For example, the neurons firing in such a way as ...
6
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1answer
2k views

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 ...
0
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0answers
21 views

Where to go next with clustered C elegans neuronal time series

I'm doing some independent research with the C Elegans nervous system (with the OpenWorm project) and was looking for some guidance as to where I should go next. Right now, I'm dealing with calcium ...
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0answers
28 views

Do ion channels block at these temperatures?

I found this paper and it says nerve axons cold block at temperatures near 0C. http://onlinelibrary.wiley.com/doi/10.1113/jphysiol.1968.sp008656/pdf Does this mean ion channels also block (due to ...
8
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2answers
243 views

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 ...
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2answers
55 views

Does the creation of memory involve mRNAs crossing the synaptic gap?

There is a diagram from a book titled "Teaching with the brain in mind". The diagram shows The diagram appears to show that the "creation of memory" involves "messages coded by RNA" moving through ...
3
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1answer
55 views

How can neurons divide without centrioles?

I have read in my studies that neurons lack centrioles. If that is so, then how is it possible that new neurons are added to our brain? Does this have anything to do with memory loss?
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2answers
3k views

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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2answers
94 views

Does caffeine actually enhance cognition?

I have heard, respectively: Caffeine measurably enhances cognitive function. Caffeine does not measurably enhance cognitive function in any significant way. Caffeine enhances cognitive function, but ...
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0answers
18 views

How much yogurt would one have to consume to have a noticeable effect on neurotransmitters [closed]

I read several recent articles that proposed a link between bacteria in our gut and neurotransmitters in our brain. For instance http://www.ncbi.nlm.nih.gov/m/pubmed/24997036/ I am curious how much ...
3
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2answers
725 views

What is the difference between clinical and non-clinical depression, and is there a term for different severity of the bipolar disorder?

I was looking for a term which describes a bipolar disorder of lesser severity. I know from experience from someone I know well, what a very severe case of the bipolar disorder looks like, when an ...
5
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1answer
85 views

How does the synaptic cleft exist?

I'm not asking why the synaptic cleft exists, i.e. what function it holds, rather how. So I know that the neurotransmitter diffuses across it, it is 20-40 nm wide and contains basal lamina (in NMJs at ...
2
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0answers
13 views

Why do fishes have both a gustatory and an olfactory system?

I would like to know if there is a know reason for which fishes (and many aquatic species) have both an olfactory and a gustatory system. As far as I know, in all fish species the chemoreceptors, ...
10
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5answers
941 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?
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1answer
19 views

Analysing the ERP (Event-Related Potential from EEG recordings) in terms of the P-300 wave

I am trying to understand how to analyze ERP (Event-Related Potentials) from EEG recordings in focus on P-300 waves. I have come up with a few questions which I hope you might be able to help with: ...
2
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1answer
35 views

Why do typical acetylcholinesterase inhibitors (like carbamates) have a greater parasympathetic effect than a sympathetic effect?

I understand that the post-ganglionic neurones of the sympathetic system are adrenergic, but surely these neurones will be excited to the same extent as the parasympathetic post-ganglionic neurones ...
1
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1answer
26 views

Why is active transport needed in repolarization?

During the repolarization phase of an action potential, the potassium ions diffuse out of the cell, and active transport begins. What I do not understand is why active transport is needed when the ...
3
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1answer
65 views

Has the human body the greatest total length of nerves of all animals?

I've read that a human body contains about 150,000-180,000 km (Pakkenberg et al., 1997; 2003) of nerve wiring in the whole body. But does this length increase with the size of the animal? For example, ...
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2answers
33 views

At what age does the mouse skull stop growing?

Unless otherwise mandated, neuroscientific research on mice is done with ~7-week old animals. There is a sort-of mantra that at this age their skulls stop growing. However, recently, I noticed a ...
6
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2answers
212 views

Dopamine paradox in schizophrenia

If there is more dopamine action in the mesocortical pathway in schizophrenia, then schizophrenics should always be in euphoric state. Instead, schizophrenics often lack motivation and do not ...
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0answers
13 views

Real unipolar neurons do indeed exist in human?

I studied that the unipolar neuron in human body are not really unipolar but they're pseoudounipolar neurons. On the other hand according to what I understood from wikipedia (neuron) there are real ...
4
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1answer
44 views

How long does a spiking signal last?

It is surprisingly hard to find information about the timing of neurons, in particular how long an action potential can contribute to the summation of a neuron. Is it on the order of milliseconds or ...
4
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3answers
75 views

what is meta-sympathetic nervous system?

I always knew about the sympathetic and para-sympathetic nervous systems, and today I was told about the meta-sympathetic nervous system, but I didn't understand well the man who told me about it and ...
0
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1answer
91 views

Can multiple overt/covert intentions produce identical EEG readings?

With sophisticated techniques likes ERP, it is possible to correlate certain EEG activity with certain overt/covert actions. What I'm wondering is: is there a risk for 2+ overt/covert actions ...
6
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1answer
75 views

What determines whether a substance can diffuse across the blood-brain-barrier?

What determines whether a chemical substance is able to cross the blood-brain-barrier via passive, transmembrane diffusion? What structurally differentiates these chemicals?
7
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3answers
248 views

Why does the human brain not overfit when training at some task?

One of the problems that occur during (artificial) neural network training is called overfitting. The error on the training set is driven to a very small value, but when new data is presented to ...
8
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1answer
62 views

Original paper about the all or none law for neurons

I am looking for the original paper about the all or none law for neural activity. I know that there is a very old article about the all or none law for mammalian heart muscle fibers, but I'm ...
10
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2answers
174 views

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 ...
0
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2answers
47 views

What is synaptic clearance?

Please explain what the term synaptic clearance means. For example, what would dopamine synaptic clearance be? It is important to me in context of dopamine signaling variation due to difference in ...
0
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1answer
45 views

How does the brain train its neural network?

One question that came up learning how artificial neural networks are working was how the brain can train its neural network? When we say we have an artificial neural network, the problem behind it ...
3
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1answer
72 views

What is the direction of current flow in myelinated nerve cells?

Is it correct to say electric current flows through the extracellular space, or cytosol of a nerve fiber during impulse conduction? I know that an impulse is actually a change of membrane potential ...
2
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0answers
30 views

Transcranial Magnetic Stimulation on science fair [closed]

My friends and I would love to make a TMS machine and apply it to make famous "god helmet". We know that magnetic stimulation may cause visions of angels, gods etc. My question is: what are the ...
48
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4answers
3k 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 ...
0
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1answer
18 views

Are cortical columns restricted to somatosensory cortical sections?

From this previous question, it seems like evidence for the minicolumn organisation of the neocortex seems to be primarily based off observations around the sensory parts of the cortex, such as the ...
2
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0answers
16 views

Pearson correlation of neural responses with it's linear estimation

I am trying to anderstand the following fact from this article (page 13): How can single neurons predict behavior Suppose I have a linear estimation of a stimulus: $ \hat{s} = \mathbf{w}^T(\mathbf{r} ...
7
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1answer
269 views

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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0answers
35 views

Why are oral cells (or tissues) more heat resistant? [closed]

When we are having meals, such as enjoying hot pot and drinking hot water, we only have a sense of "warm" in our mouth, or even along the organs in alimentary canal. But when we put our fingers into ...
7
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1answer
114 views

The mechanism of mechanoreception?

I am interested in knowing the molecular mechanism behind mechanoreception/mechanotransduction (i.e. mechanism behind receptor potential generation on mechanical stimulation). I know that most ...
4
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3answers
447 views

What exactly is the neural receptive field?

Neural receptive fields map the spatial or temporal distribution of the data to individual neuron excitation, if I understand correctly, but I do not understand if receptive fields (especially in the ...
2
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1answer
88 views

Anatomy of nervous system's sensory pathways

When I touch my hand on a hot stove, I feel pain. I'm interested in knowing all the main "endpoints" (components/parts of the body) that are involved in relaying this pain signal. As I understand it ...
6
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1answer
473 views

Relationship between nerves and axons

I just wanted to get a realistic viewpoint of our nervous system. I understand arteries and veins, but I wanted to know how similar our nervous system is to that? I understand we have neurons ...
3
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1answer
68 views

spinal cord lesion and result in somatic sensation

Jimbo suffers a lesion to the entire right half of the spinal cord at the T6 level. A few weeks after his injury, his doctor tests his right and left legs for somatic sensation and tone. fill out her ...
7
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1answer
60 views

What stimulates a nociceptor?

For instance, when pressure is applied to the skin, what determines how much pressure results in nociceptor stimulation. And when a sharp object pierces the skin, why is pain, rather than simply ...
11
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1answer
253 views

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 ...