Questions tagged [neuroscience]

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

182 questions with no upvoted or accepted answers
Filter by
Sorted by
Tagged with
1
vote
0answers
44 views

3D Object Modelling in the Brain

Could somebody point out the neuroscience literature dedicated to the modelling of 3D objects in the human mind? I'm interested in the brain regions, and particularly the details of the circuitry, ...
1
vote
0answers
38 views

Drinking and eating ability of infants soon after birth

How do infants know how to eat, drink without being taught? How do they get this ability soon after birth?
1
vote
0answers
46 views

Distribution of sodium–potassium pumps

How are sodium–potassium pumps distributed over the membrane of a neuron? Where are the most, where are the fewest? Or does this dependent on the type of neuron? Are there known and understandable ...
1
vote
0answers
70 views

What is the degree distribution of synapses per neuron in the human brain?

I believe the mean number of synapses per neuron in the human cortex is around 6000. What is the distribution around that average, either for the cortex or for the whole human brain? E.g., is it ...
1
vote
0answers
75 views

Longest pathway from sensory to motor neurons

How long is the longest pathway a neural signal can take starting from a sensory neuron and ending at a motor neuron (without loops)? [This is a purely theoretical question concerning only the ...
1
vote
0answers
227 views

Can nerves in the human body be spliced with a form of electric wire?

This may be a ridiculous question, and is hypothetical, but I'd like a well-supported answer. Is it possible to splice copper wire (for example) into the human nervous system? Would the charge ...
1
vote
0answers
269 views

Why bipolar neurons in retina transfer information via graded potentials?

Why should bipolar cells prefer graded potentials to action potentials? My attempt: I know that graded potentials are better in processing information since stimulus is directly proportional to ...
1
vote
0answers
234 views

Nature of transmarginal inhibition

I've recently become aware about existence of such phenomena. From my naive point of view, I understood it as existence of two general types of neural cells, one type serve inhibitory purpose and the ...
1
vote
0answers
495 views

What is a unitary post synaptic potential?

I am reading the paper Cooperative subnetworks of molecularly similar interneurons in mouse neocortex and have encountered the term: "Unitary (excitatory or inhibitory) post synaptic potential". I ...
1
vote
0answers
39 views

Do neurons feature a collective “resistance” to firing too often beyond the refactory period?

My understanding is that neurons are prevented from firing too often by a 2-part refactory period: an immediate inability to fire again for a period of time followed by an increased threshold for ...
1
vote
0answers
14 views

What motivation is there to create general, cross-species neural models which account for the variation between species in different environments?

The main components of human neuroanatomy have been mapped out. What attempt has there been to map a broad (many-species) spectrum of functional parts of the nervous system? Such a mapping could be ...
1
vote
0answers
129 views

What is the derivation of the rules of proportionality between axon conduction velocity and diameter?

We have been told that in myelinated fibres, conduction velocity is proportional to the diameter of the axon. In unmyelinated fibres, velocity is proportional to the square root of the diameter. Can ...
1
vote
0answers
26 views

Cytochrome Oxidase activity in neuronal cells

The abstract of this article says "...the entire neuron is often not metabolically homogeneous; most of the oxidative activity is usually found in dendrites." Why would the activity of cytochrome ...
1
vote
0answers
98 views

How screeching affects the body?

Most times when I hear a screech (such as moving a sharp object on a chalkboard thereby causing such unpleasant noise), my body twitches. There are also other unpleasant sounds that causes the ...
1
vote
0answers
42 views

Is the enteric nervous system found only in vertebrates?

The enteric nervous system is distinguished by being autonomous from the central nervous system and capable of independent action, such as the peristaltic reflex. For this reason the the intestines ...
1
vote
0answers
38 views

Forgot to cool slides before washing

I just finished an immunofluorescence experiment and I'm wondering what went wrong. The tissues seem dimmer than they should be. One mistake I made was: I completed the antigen retrieval step, in a ...
1
vote
0answers
105 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 ...
1
vote
0answers
73 views

Distribution of synaptic connections

What is the roughly the distribution of the various synaptic connections in the brain. Consider the following types: axoaxonic synapse between the axon of one neuron and the axon of another neuron. ...
1
vote
0answers
38 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 ...
1
vote
0answers
41 views

Gastroenteritis virus causing mutation of the Enterochromaffin cells

I am working on the solution to a worldwide problem: IBS or chronic diarrhea following a viral gastroenteritis infection. I think I have an answer. The only missing piece to the puzzle I found in a ...
1
vote
0answers
81 views

Systematic anticoagulant injection after a CVA

Since most of the cerebrovascular accident are ischemic ones, would it be usefull to have anticoagulant everywhere (we already have AEDs everywhere) so that everytime someone would have symptoms of a ...
1
vote
0answers
46 views

Stress regulation in mosquitoes

I was just trying to understand how in insects, specifically mosquitoes does the process of emergency responding, stress regulation take place? Or in simpler words how are flight, fright and fight ...
1
vote
1answer
63 views

By what physiological mechanism do we not feel microbes (bacteria, etc.) living on our skin?

Background I know our bodies have a handful of ways to threshold our awareness of sensory stimuli: Neural density Sensory acuity I assume really tiny stimuli could fit between receptors e.g., ...
1
vote
1answer
56 views

Is the strength of presynaptic stimulus on the postsynaptic neuron affected more by the dendrites, or the cell body?

Is the strength of presynaptic stimulus on the postsynaptic neuron affected more by the properties of the dendrites & axon terminals, or the cell body & axon? Two years ago I asked a question ...
1
vote
1answer
192 views

How do nerve impulses travel so quickly?

Nerve impulses must travel incredibly fast to achieve the functions they do. However, I have been taught that sodium ions move down the axons by diffusion (thus causing depolarisation of the next part ...
1
vote
1answer
9k views

How long does it take for dopamine to reach normal levels after a significant drop?

The building block sequence for is: Phenylalanine << Tyrosine << L-Dopa << Dopamine. It’s produced in only a few, very specific regions: Substantia Nigra and the Ventral Tegmental ...
1
vote
1answer
179 views

How does the brain manifest and realize the intention to resist sleep?

The question title says it all. What happens in my brain when I resist sleep? I would appreciate explanations on neurotransmitter changes, what areas of the brain activate to resist sleep, what can an ...
0
votes
0answers
30 views

Phantom Limb | Is that even possible?

I am fascinated by the fact that an amputee can control their robotic arm by thinking of the actions they would normally execute when the limb was present. The mind sends signals to the nerve endings ...
0
votes
0answers
8 views

When assessing a threat, does the amygdala compare the stimulus to memories of the amygdala or the hippocampus?

Two excerpts from the one article. My understanding of this excerpt is that the amygdala is using its own memories: The amygdala learns how to respond to various stimuli based on it’s reference to ...
0
votes
0answers
17 views

Can we say that the source of the most circulatory regulation in the human is the nervous system?

local regulation of blood flow and Baroreceptors, both stimulate the neurons and send messages to the brain. so can we say that the source of the most circulatory regulation in the human is the ...
0
votes
0answers
17 views

Why are the sympathetic and parasympathetic axons different, in terms of presynaptic and postsynaptic length?

Does the parasympathetic system have a long presynaptic efferent axon because it takes a great distance to reach target organs from the brain stem or sacral region of the spine? Does the sympathetic ...
0
votes
0answers
13 views

Alzheimer's datasets highlighting role of individual genes

A question to the folks who studies Alzheimer's disease here. My colleagues and I have developed a new program that predicts the master regulators based on transcriptomic changes (yes, another one). ...
0
votes
0answers
18 views

Adding potassium outside of neuron: Hyper- or De- polarization?

At rest, the equilibrium potential for potassium given by the Nernst equation is ~ -80mV. Since the cell is mainly permeable to potassium, this is the reason for the cell membrane's rest potential to ...
0
votes
0answers
19 views

Doubt related to nerve impulse transmission

Naturally, the extracellular fluid has more sodium ions and the axoplasm has more potassium ions. Since there are more potassium leakage channels than sodium leakage channels on axoplasm, it is more ...
0
votes
0answers
120 views

What brain regions consume the most energy?

It's well known that the human brain consumes roughly 20% of the body's energy, and that grey matter is much more energy-intensive than white matter. Beyond this basic information, it seems difficult ...
0
votes
0answers
9 views

Does the brain absorb heme and non-heme iron differently?

I know that for the brain to absorb iron, the iron must first pass through the blood brain barrier. Is this absorption different for heme and nonheme iron?
0
votes
0answers
13 views

How does lactic acid cause muscle twitching?

It is well-known that lactic acid buildup (often caused by workouts) causes muscle twitching. Does anyone know HOW lactic acid achieves that effect?
0
votes
0answers
7 views

Which hormones, metabolites, or other molecules build up as the day progresses, other than melatonin and adenosine?

Melatonin and adenosine reach peak levels around midnight/bedtime. I was wondering what other molecules also buildup as the day progresses. Particularly molecules that affect the CNS and/or immune ...
0
votes
0answers
16 views

Would it be possible to determine the strength of each neural connection in a connectome data set?

I understand that a connectome is a map of connections between neurons. Would it be possible with current day technology to create a more detailed map that gives not only the connections themselves ...
0
votes
1answer
28 views

Why is the ratio between action potential and threshold value called the 'safety factor'?

"All­or­Nothing Principle. Once an action potential has been elicited at any point on the membrane of a normal fiber, the depolarization process travels over the entire membrane if conditions are ...
0
votes
0answers
24 views

Is relative timing of signal transmission between neurons along axons and through synapses relevant in the brain?

A neuron may be part of a nerve connection between two endpoints, transferring a signal that is not very sensitive to variations in signal propagation speed. But a neuron inside a cluster of ...
0
votes
0answers
48 views

Long-term potentiations that last for a lifetime

One reads more often than not that long-term potentiation has been reported to last for as long as several weeks LTP is persistent, lasting from several minutes to many months and most sources seem ...
0
votes
0answers
16 views

Typical firing patterns of neurons in the default mode network in resting state

Inspired by the Wikipedia article on the default mode network where I read: Hans Berger, the inventor of the electroencephalogram, was the first to propose the idea that the brain is constantly ...
0
votes
0answers
17 views

Functional roles of firing patterns

Eugene Izhikevich reports – e.g. here – a plethora of neural firing patterns: My question is two-fold: Is there an overview which types of neurons are capable of (and typically exhibit) ...
0
votes
0answers
57 views

Can brain activity be restored after being stopped, assuming no cellular damage?

I was reading about cryonic preservation recently. In a separate place on the Internet, I've read that once brain activity stops and brain death occurs, the person is dead with no hope of recovery. ...
0
votes
0answers
42 views

Factors behind frequency of action potential

I understand that the amplitude of an action potential is not influenced by the strength of the stimulus. I also understand that the perception of the strength of the stimulus depends on the frequency ...
0
votes
0answers
37 views

Can IPSPs produce an action potential?

This picture was taken from Purves' Neuroscience, chapter 5: Image (C) shows a inhibitory postsynaptic potential whose reversal potential "goes" to the action potential. If two or more IPSPs occur, ...
0
votes
0answers
23 views

What is the purpose of descending auditory signals from the brain?

What might the purpose be of the brain having descending auditory signals from the brain? My textbook is very vague about this and I am just curious.
0
votes
0answers
30 views

What are the advantages of bidirectional signalling in electrical synapses?

Electrical synapses are known for being very fast at communicating with other neurons. (1) What I often see in articles about electrical synapses is that they are bidirectional.(1) This is seen as a ...
0
votes
1answer
32 views

What determines the influx of calcium ions in the voltage-gated ion channels?

Calcium channels play a crucial role in neuronal signaling by helping the synaptic vesicles to fuse through the synaptic active zone and release their neurotransmitters. My question is, at a given ...