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

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What is in the space between neurons in a brain?

When neuron animations are displayed, there are frequently seen neurons, axons arranged in a lattice with a lot of empty space between. I'm interested if there is indeed empty space in the brain, or ...
2
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2answers
54 views

Converting fmri data to association matrix

I am currently working on a new tool for the analysis of (large) weighted networks. Association matrices (correlation matrices) as obtained from fMRI data are perfect examples of the kind of data I am ...
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1answer
102 views

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 ...
3
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0answers
36 views

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 ...
2
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2answers
81 views

Parallels between pixelized image and the human retina

On Wikipedia it is explained that the human eye has a certain 'resolution'. Does this mean that the retinal image consists of pixels? If yes, what shape would these pixels have?
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2answers
91 views

What triggers programmed cell death in humans (from outside the cell)?

What triggers programmed cell death in humans? Is it decided by the brain (for the entire body)? Or is it a local decision of a cell by its environment? Something else? I realize that there might be ...
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0answers
18 views

Why after physical activity I see flickering concentric circles? [duplicate]

After prolonged hard physical exercise such as running uphill I sometimes experience rapidly vibrating black-and-white concentric circles for a few minutes, looking like a sinusoidal zone plate, small ...
5
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1answer
32 views

What happens when someone is stung by a jellyfish?

What happens in the human body when someone is stung by a jellyfish; namely a box jelly. Judging by what I have heard about the stings I'm guessing that they involve a neurotoxin. But what is ...
9
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2answers
777 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 ...
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0answers
15 views

Retinal eccentricity to colour sensitivity [duplicate]

Colour perception goes out to 50 degrees but is the sensitivity to RGB. Question is it the same in the four quadrants of the retinal field? That is if the red colour sensitivity eg is 30 temporal ...
6
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1answer
76 views

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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2answers
85 views

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 ...
3
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1answer
44 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 ...
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1answer
168 views

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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3answers
982 views

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.
8
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1answer
110 views

Neuroendocrinal mechanism of parturition

My book reads, "The fetus signals that it is mature by secreting certain hormones that diffuse across the placenta into mother's blood and cause the secretion of oxytocin from her posterior ...
4
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1answer
41 views

Are there any known health benefits / risks from milliampere current (0.1-2 mA) on forehead?

This is about devices like that sold by foc.us that allows user to apply a small current on a specific part of the forehead. For the sake of this question I use the foc.us "gamer" model as example. ...
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2answers
2k 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).
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2answers
226 views

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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2answers
55 views

Action potential changes in low sodium concentrations but constant osmotic pressure

If I bathe a squid axon in a fluid that has high sodium concentration , why does the duration of action potential decrease compared to a control experiment in low sodium bath but maintained at the ...
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3answers
176 views

Can human brain memory be removed by EMP?

The human brain is the most complicated human organ so it is hard to examine it completely but based on what we know do you think (or do you know from some source) if a human memory can be removed by ...
5
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1answer
60 views

Are there baby drinks closer to breast-milk?

Many women cannot or will not feed their children with breast-milk. It is my understanding breast-milk has many advantages over formula. Some psychological like oxytocin and some physiological like ...
0
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1answer
49 views

Satisfication with irrelevant things [closed]

I am not sure if this question is better suited CogSci.SE so please tell me. My question is why are we satisfied when we get things that aren't useful in any important way? For example, relating to ...
9
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1answer
1k views

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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131 views

Can a single axon propagate multiple simultaneous action potentials?

I have not been able to locate any research that indicates whether a single axon of a neuron or nerve cell can conduct multiple simultaneous (i.e. spatially separate) action potentials. I am aware ...
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1answer
58 views

Spinal cord injury bypass

When the spinal cord is damaged, the connection between the brain and some part of the body may be lost. To restore this connection, researches are considering either: Repairing the damaged area so ...
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2answers
194 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 ...
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2answers
134 views

Why does anxiety cause diarrhea or constipation?

Anxiety sometimes cause diarrhea, sometimes constipation, and sometimes both. It's interesting because it seems their underlying neurophysiology is somehow different. What are underlying physiological ...
7
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1answer
84 views

Can rapid eye blinking induce epileptic seizures?

Photosensitive epilepsies are characterized by visually-induced seizures. Flashing-light stimuli are known to induce seizures in some (but not all) patients. My question is whether people with this ...
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1answer
77 views

Do voltage-gated calcium channels affect neuronal conduction speeds?

We have a hypothesis that a drug may block the voltage-gated calcium channels (VGCC) in annelid worms. We are wondering whether there are any correlations between VGCCs and neuron conduction ...
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2answers
45 views

Hydrophobia Outside of Rabies?

RELATED: Why does rabies cause hydrophobia? Agony, Hydrophobia and viruses in the light of evolutionary principles Has hydrophobia been found outside of rabies? I have only seen it ...
2
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1answer
52 views

What percent of the population has some form of synesthesia?

Data I am trying to get my hands on: What types of synesthesia (e.g. Grapheme-color synesthesia, Chromesthesia, etc.) are most common across the population? What percent of population has that ...
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1answer
19 views

Neuron Growth and Regeneration

Are nerves and/or neurons able to grow and repair after damage, but not regenerate? Is this specific to humans? I have heard of people being paralyzed, but after much therapy are able to use their ...
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3answers
536 views

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?
2
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1answer
69 views

Carrying or packaging capacity of SAD B19 dG rabies virus

I'm wondering about the carrying capacity also referred to packaging capacity or loading capacity (how many base pairs can be packed efficiently into virions) of the pseudotyped rabies virus SAD-dG as ...
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1answer
51 views

Effect of closed eyes on balance?

Suppose you want to stand on one leg. Doing it eyes open is not that difficult, but doing it eyes closed seems to be difficult. Why?
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3answers
73 views

If my brain lost all of its activity for a moment, would my memory be gone too?

I can't remember which question it was, but in the past here, it was explained to me that memory is actively stored in the brain, rather than "physically". Meaning, memories are made up of the brain's ...
4
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2answers
57 views

Can the human eye distinguish colors in the periphery?

In the back of my mind I have the idea that human eyes can't notice the color of objects in the far periphery, and that any subjective perception of colors is done by the brain that tries to fill in ...
2
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1answer
37 views

Kinesin-5 / cytoplasmic dynein spatial density distribution in neurons

Is there some way to experimentally determine the density distribution of Kinesin and Dynein in a Neuron? Fluorescence labeling would be impossible(?) as GFP markers would probably alter the motor ...
0
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1answer
42 views

How does anger relate to blood pressure?

Anger is an emotion generated by neural processes in the brain and is associated with elevated blood pressure. How can an emotion, which is totally related to brain, result in blood pressure changes?
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More vectors for inducing neurodegeneration (reduction in synaptic plasticity) in D.melanogaster

I've just finished a project on loss of synaptic plasticity in Drosophila melanogaster larvae with uas control gal4 sensor for cAMP expressed in the motor neurons. I induced neurodegeneration through ...
3
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2answers
56 views

Is there any research on how accurately people can follow a beat?

I'm currently helping develop a rhythm game, and as part of the scoring system, I'd like to make scores and ranks based more on accurate pattern recognition rather than hitting notes very exactly on ...
2
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1answer
46 views

What can myelination tell you about the evolution of sensory receptors?

I am reading Avi Chaudhuri's Fundamentals of Sensory Perception and wondering if the information given about the somatosensory system could tell us anything about the way it evolved. It seems (at ...
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1answer
26 views

Is Norepinephrine beta2 adrenomimetic?

I know that it has alpha1, alpha2 and beta1 effects. It has beta2 receptor where epinephrine can effect. However, to say that it is beta adrenomimetic, I am not sure. That is ligand binding beta2 ...
3
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1answer
44 views

Cross section of actin network in neurites

for a simulation I am developing I would like to know how the actin network in neurites is distributed. Is actin confined to the periphery or is the whole neurite shaft containing actin with a rather ...
10
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1answer
315 views

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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1answer
724 views

What are the advantages and disadvantages of being ambidextrous?

What are the advantages and disadvantages of being ambidextrous? We have two hands and we nearly can't use one and this seems like a weakness, and a stupid one when you first think about it. But ...
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2answers
108 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
83 views

What are the physiological roles of Hydrogen sulfide?

I am thinking why hydrogen sulfide has its effects in the body. For instance, it is one Salmonella's virulence factor. I am not sure if such a balance equations holds H2O + H2S ←→ ... Actually, I ...
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1answer
64 views

How small does a nanobot have to be to “swim through the brain” and access any neuron it wants to?

I read on this question What is in the space between neurons in a brain? that there is actually not much empty space in a brain. But my question is slightly different. Is there a visual demonstration ...