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

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1answer
157 views

Effect of pupil responses on the electroretinogram

The electroretinogram (ERG) is generally considered to reflect the retinal processing of a light stimulus, typically a photoreceptor response followed by secondary neuronal activity. I am wondering ...
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2answers
50 views

What features cause mechano sensory adaptation?

In relation to mechanoreceptors (e.g. pacinian corpuscles), what stops a constant stimulus from producing action potentials? I understand that adaption is used to filter out stimuli that aren't ...
3
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2answers
206 views

What happens in the synapse when cocaine administration occurs in the human brain

As far as i know when you accept cocaine in your blood some cocaine molecules reach some synapses in your brain and fill some Reuptake tunnels preventing the cell to simply "do not know that fired ...
3
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0answers
38 views

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 ...
3
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1answer
25 views

Safe parameters for external nerve stimulation using electrical impulses

Introduction I've recently stumbled upon David Eagleman's TED talk on the concept of sensory substitution and addition. Being the most inspiring thing I've seen on the internet for the last few ...
6
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1answer
28 views

Behavioral change in dolphins during different hemispheres activity periods?

It is known that dolphins never sleep in the sense that we do, instead they have one hemisphere of the brain sleeping while the other one is awake. I wonder, do they show observable changes in ...
4
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1answer
57 views

How pain can stimulate the vagus nerve

I'm trying to find out why a prompt, severe, short pain is causing a stimulation of the vagus nerve. What could the physiological explanation be? Is that because the pain is triggering the ...
6
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2answers
108 views

Is there a biological neuron that spikes in response to hyperpolarizing currents?

As some background I've been building Electrophysiological models of neurons, and in the process stumbled upon a model, that in all respects is biologically plausible, but has a bizarre property I ...
7
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4answers
852 views

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? ...
2
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1answer
24 views

Why are skin tactile receptors considered to be phasic receptors?

A phasic receptor by definition is one that quickly adapts to change. In terms of neuron firing, this means that it does not trigger another firing because the receptors are used to the stimulus. But ...
6
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1answer
143 views

How is color information transmitted from the eye to the brain?

Is color information sent from the eye to the brain frequency-modulated, or are different colors transmitted by different axons? I know that each ganglion cell is connected to multiple ...
5
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1answer
47 views

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 ...
6
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1answer
328 views

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 ...
6
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2answers
115 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 ...
2
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1answer
10k views

What are the functions and differences between axons and dendrites?

My textbook doesn't do a very good job of pointing out what the differences between the two are. It basically mentions axons only in the same breath as the synapse (that synapses are the endings/tips ...
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0answers
21 views

Immediate Early Genes during sleep

In Neuroscience 3rd ed by Bear et al. on page 607, immediate early genes are described as related to changing synaptic strength, yet have decreased expression during sleep. The explanation given is ...
7
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4answers
492 views

Is there a correlation between total neurons and intelligence?

Thanks for looking. First off, I am not a biologist, just a curious layman, so I apologize in advance if this isn't a "good" question. Please don't downvote me into oblivion. I read today that the ...
6
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1answer
337 views

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 ...
2
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1answer
55 views

How can TMS induce enough depolarization to cause an action potential?

Creating an action potential needs at least tens of mV potential difference across the membrane to occur. But the membrane is really thin, surely less then 0.01µm (some reference give 25A). Then the ...
4
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1answer
83 views

What are the total number of action potentials in the human brain?

Is there an approximate figure of the total number of action potentials in the human brain? It's my understanding that there are ~ 60 billion neurons in the brain with ~ 100 trillion connections ...
3
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0answers
50 views

How we share pain?

When somebody else tells me about his or her itching or pain in some specific body part I sometimes begin to feel similar feelings. I can think of about three explanations: I feel pain all over my ...
4
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1answer
58 views

What (open) software there are for simulating behaviour of human (cortical) neurons?

Is there any reliable open-source software for simulating the behaviour of human cortical neurons? I am looking for serious software, so let's assume I have access to a computer with more than 10,000 ...
7
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3answers
192 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?
2
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1answer
45 views

Is it possible to process electrical signals from the brain and interpret the results as exact thoughts?

If the brain uses extremely low voltage signals to communicate (from what I understand around 100 mV), what sort of breakthroughs would be necessary to intercept these signals and interpret them as ...
3
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0answers
18 views

Immediate stroke/seizure Therapy

Can an oncoming stroke/seizure, be stopped by a setup consisting of a brain-computer-interface (BCI) that immediately detects the variation in wave-form, and then another machine that neutralizes the ...
4
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0answers
69 views

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 ...
3
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1answer
26 views

What is an auditory upward sweep?

I was reading an article in nature communications, when I came across this sentence: "The ‘match’ rule was indicated by either a blue circle or a auditory upward sweep".So I tried googling what was an ...
9
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2answers
110 views

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 ...
4
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1answer
161 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 ...
6
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1answer
130 views

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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44 views

Why did the Brain develop in the front in most organisms?

I was wondering my most, well pretty much all organism with a brain have it right in front of their bodies or at the top.
0
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1answer
25 views

Is it a medical condition to not able to recall the word in a language while having a conversation [closed]

While having a conversation it happens to some peopl that clearly they know there exists a perfect word to be used but can not recall it during the conversation in real time and hence forced to use ...
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2answers
1k views

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
59 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 ...
7
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1answer
128 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
45 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
94 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
98 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 ...
0
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0answers
22 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 ...
4
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1answer
35 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
2k 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 ...
5
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1answer
98 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 ...
3
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1answer
52 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 ...
8
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1answer
200 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 ...
9
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3answers
1k 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
51 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. ...
26
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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).
4
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2answers
337 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 ...