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

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What are the factors that control the speed of propagation of neuronal signals?

If we consider an analogy between a wire and a neuron there may be some resemblance between the factors controlling the data flow rate. For example the increased width of wire leads to decreased ...
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139 views

How is information sent from limbs to the brain exactly?

Say you have a needle, and you poke a very specific area on your left thumb. A signal gets sent from that nerve up your spine and into your brain. How does the brain know exactly where this signal ...
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817 views

Neuromediator, Neuromodulator, Neurotransmitter?

Of these three words, perhaps Neurotransmitter is the most obvious. I took a look at Wikipedia page for Neuromodulation and found that this is pretty similar to Neurotransmitter too. I guess ...
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189 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 ...
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107 views

Do skull bones have pain nerves (nociceptors)?

I recently attended an awake brain surgery for deep brain stimulation and it seemed to me that only the skin surrounding the drilled hole got local anaesthesia. I know that the brain itself does not ...
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111 views

Benefits of CLARITY?

What are the benefits of CLARITY over this technique that was published more than a year earlier? Of course the second technique needs a fancier microscope that is likely more expensive and requires ...
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66 views

Can 'hardware' thermalization explain memory decay?

Often we are able to memorize very precise bits of information (exact addresses, birthdays of inlaws, number of dirty socks under the bed), but over time our recollection tends to become fuzzy. We no ...
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190 views

Is there a maximum pain threshold?

Is there a maximum threshold of pain a Human can experience, beyond which point there is no noticeable difference? I ask this question in part to better understand the definition of pain and its ...
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138 views

Neuroscience of temperature regulation and perception

The hypothalamus is known to be important in the regulation of body temperature, but I'm curious whether anyone knows about the neurocircuitry of perceived temperature. It seems like there could be a ...
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1k views

SPINAL CORD: Do the axons from white matter synapse with the cell bodies in grey matter?

After wading through a sea of information, I understand the main differences between the white matter and grey matter of the spinal cord. I know that white matter contains myelinated axons in the ...
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35 views

How can I determine the purity of cells isolated from rat brains if I cannot use FACS, Immunohistochemistry or SEM anaysis?

Please help. I know how to isolate the different cells (astrocytes, other glial cells, neurons and synaptosomes) from brain tissue using a Ficoll-based separation but how do I determine the purity of ...
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25 views

What is meant by drug tolerance?

What is meant by drug tolerance? This question is in my biology textbook for IGCSE and I have no idea what drug tolerance is. It would be very helpful if someone could clarify. Thank you.
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181 views

Will neurons live after the death of a human? If so, how long?

I don't know if this is correct or not, but I have heard this from a friend and I want to get a clear explanation about this.I hope there is some one who can help me.
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178 views

Ventral stream pathway and architecture proposed by Poggio's group

Please can you give me a very brief explanation about all functions in the ventral stream architecture summarized in this figure: This figure is from Serre et al.'s A quantitative theory of ...
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52 views

Number of MHCs in neurons

I have read that neurons have proportionately less MHC molecules than other cells of the body. What is the advantage of this?
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616 views

Why Do Nerve Signals Get Crossed?

First off, I don't know if this is a normal healthy thing to occur. There have been many times where I have an itch on say my arm and I scratch it, only to feel the scratching elsewhere on my body. I ...
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1k views

Is “tonic activity” common for neurons firing in the brain?

I've been reading about Dorsal Raphe Nucleus, a serotonin- rich part of the brain. I noticed mentioning of "tonic activity" - regular pulsing that releases neurotransmitters. On top of this "tone" the ...
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3answers
267 views

How is propagation of action potentials terminated once the “message” has been sent/received?

I'm thinking about neurons in the brain that are used for "thinking". As I read about action potentials, I see that an Axon is connected to a Dendrite of a neighboring cell and that there are ...
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75 views

Text/resource with information on all skeletal muscles and their motor units

Something analogous to an encyclopedia on baseball players with a list of all thier stats would be ideal. I'm not looking for just generic muscle names, locations and illustrations. Good answers ...
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199 views

Does body mass have a bearing on reflex speed?

A reflex is an unconscious action in response to some specific stimulus, e.g., blinking an eye, or pulling the hand away from a hot pin I know from school biology, and reading online that withdrawal ...
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37 views

Can a postsynaptic neuron 'shut itself off?

I am an amateur interested in neuroscience and was curious whether there is a process by which a neuron or group of neurons would close their receptors and stop receiving signals from specific ...
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106 views

dopamine paradox in Schizophrenia

If there is more dopamine action in the mesocortical pathway in Schizophrenia, then the patients should always be in euphoric state. But instead patient lacks motivation and don't want pleasure. Why?
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189 views

How does the brain know where a signal came from? What is the addressing system

I am an electronic engineer so I am thinking about this from an electronics outlook. How does the addressing system work, As I see it, the nervous system is small parallel branches attached to larger ...
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234 views

What happens in your brain when you receive information which causes you to bristle?

I'm talking about moments when you watch a film and you bristle, or when you listen to music, etc. What kind of neurotransmitter flow changes?
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120 views

Hearing and neurons- do ears have a sampling period?

From what I have read, outer hair cells in the human ear amplify incoming signals and inner hair cells "pick-up" the signals and generate action potential. However, neurons have refractory periods ...
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147 views

Which Receptors are Involved in the antidepressant effects of SSRIs?

From what I've read the major receptor subtypes involved in the antidepressant effects of SSRIs are: 5-HT1A 5-HT2C 5-HT3 5-HT6 Please cite journal articles to back up your claims, I don't want any ...
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46 views

How does Serotonergic (5-HT2A mediated) Psychedelia work?

How does serotonergic (5-HT2A specific) psychedelia work? I've read that there are some theories that it might involve the induction of a glutamate release in certain regions of the brain involved in ...
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Do neurons secrete multiple neurotransmitters, or just one type?

I know that neurons communicate between each other by filling the junction between dendrites with neurotransmitters. What interests me is if a single neuron only works with one type of ...
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678 views

Physiological indicators of happiness and well being

If I understand it correctly, levels of serotonin in the brain can indicate if a person is happy. What other physiological measures indicate happiness or well being for a humans? I am looking for ...
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209 views

Does the speed of electrical impulses through neurones decrease with age?

From what I read on the NatGeo app, it stated that the speed of the electrical impulses that are sent by a neurone will be approximately 332 kilometers per hour. Will the speed of this electrical ...
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250 views

Why apes started to contemplate and become altruistic? [closed]

I was asking this first on philosophy forums, but it is suggested, that answer could be found from evolutionary view of point, so here we go: Again my question raised when thinking of myths, their ...
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30 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 ...
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152 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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58 views

The Operation of tuning in the S1 layer of ventral model

According to my previous question in ventral Stream pathway and architecture, I want now to get a brief example about how the S1 layer is constructed. In other words, how all the simple units are ...
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63 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 ...
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What Role Antagonists Play in the Study of Drugs?

I am pretty unfamiliar to pharmacology. I'm doing a research on drug abuse, particularly opioids' mechanism of action. I encountered several times evidences that come from studies using antagonists ...
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3answers
466 views

Is there such thing as “half-life” of dopamine?

If a dopamine is released at T=0 and binds to receptor D2, what determines the time when the concentration of this neurotransmitter bound to the receptor reaches half of the original concentration? In ...
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1answer
214 views

Neurons with thousands of connections: where are the extra connections coming from?

If every neuron has only one Axon but can can have thousands of (or let's say, even just ten) incoming Axon connections via its dendrites, where are the extra connections coming from? It seems to ...
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91 views

Thoughts precede neuron firing or vise-verse?

I am at the verge of submitting a paper on 'scientific explanation of reality' to an international philosophy body. First submitted draft was returned by the evaluation expert, asking me to re-submit ...
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173 views

Mechanical cause of loss of consciousness

Consciousness is an electrical and chemical interaction in the brain, caused by neurons firing and chemical interactions. How does a mechanical "force" cause this to stop working? i.e. How does a ...
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676 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 ...
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1answer
307 views

How exactly does marijuana damage brain cells?

I've heard that THC can cause permanent damage to brain cells. I've also heard this reffered to anti drug propaganda. Another theory i've read is that temporary effects reduce intelligence but long ...
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106 views

Why does chewing enrage me?

Whether it's snacking on chips, munching on salad, or simply chewing gum, when I hear someone do it within an earshot, it drives me completely bonkers! It doesn't matter if it's my girlfriend, my ...
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174 views

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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255 views

Action potential and sodium channels

In this video on electro tonic potential, the tutor says that when the potassium channels open the potential drops from +40mV to -80mV, where the sodium channels have already closed at +40mV. Now in ...
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67 views

What will happen if we expose the brain to an intermittent light?

If a brain is exposed to an intermittent light are specific areas going to fire? If yes, which of them? Is there any experiment about this?
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528 views

What is a cortical circuit?

I have read about cortical circuits in the context of connectomics (e.g. any example here) and computational neuroscience (e.g. any example here), but a simple Google/Wikipedia does search not show an ...
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1answer
41 views

Biological advantage of electric synapses

Electric synapses are synapses that do not process information but simply foward one action potential from one neuron to the next. There are no neurotransmitters, no inhibitory and exitatory ...
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1answer
52 views

Why do the neuron pathways decussate?

I learn about the brain right now, and there are crossing of neuron pathways everywhere; in the thalamus, the medulla oblongata, the pyramidal tract... And I don't understand why? What is the reason ...
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61 views

What is the creature with the lowest neuron count that demonstrates cognition beyond reflexes?

I'm under the impression that nematode worms just perform the same scripted actions over and over again in response to specific stimuli. They have 302 neurons. Chimpanzees display problem solving ...