Questions tagged [neuroscience]
The study of the structure and function of the nervous system and its components.
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How fast do we fall asleep?
When looking at the process of sleeping, most research I find point to a group of mutually inhibitory cells which form a sort of biological "flip flop." There's cells that promote awakenness and ...
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1answer
33 views
How are peptide neurotransmitters important for the nervous system?
How essential are peptide neurotransmitters for the nervous system? I know that some peptides are hormones which can also act as neurotransmitters in the body, and that they have multiple functions (...
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Do we know how to induce brain plasticity?
I assume the answer is "no", since recovering from strokes is still slow and learning to play violin as an adult is considered hard. But I would be interested to hear whether this is an active topic ...
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What are the chemicals in the gap at a synapse? [duplicate]
I am learning about (introductory level) biological psychology and the synapse structure came into mind. I do understand that neurotransmitters are transmitted between two neurons via the synapse ...
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1answer
49 views
Why/how does exposure to noise cause cochlear hair-cell loss?
I am trying to understand why listening to loud music - e.g. concerts or earphones at high volume damages hearing.
According to the National Institute on Deafness the cause is physical.
Most ...
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17 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.
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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 ...
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How do we know there aren't vital chemoreceptors in the hair cells of our ears, and that the brainstem is responsible for 80% of the breathing drive? [duplicate]
How is the response from chemoreceptors tested, such as how do we know the brainstem is responsible for 80% of the breathing drive, and that the inner ear is not responsible for 60% of it, instead?
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Is sexual desire stronger in men than women?
Usually in popular culture it's considered men sexual desire is stronger than women. This seems to be congruent with the availability of sexual related items for men and women, such as magazines, ...
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Why is there no solid evidence (histological, fMRI) that the vestibular hair cells of the inner ear contribute to 53% of the respiratory drive?
There are these papers which strongly imply that the inner ear hair cells, and not the medulla, is primarily the driving factor in the CO2 drive reflex
https://www.ncbi.nlm.nih.gov/pubmed/21130842
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1answer
16 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 ...
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1answer
21 views
What happens when the conductance of a sodium channel increases?
My intuition is that, since the concentration of sodium within a cell is higher than the extracellular concentration, when conductance increases, this corresponds to the channel being open and means ...
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Are neurotransmitters part of the endocrine system?
I was speaking with a substitute teacher of mine, and we were discussing whether neurotransmitters are part of the endocrine system or not. My class just spent an entire semester on the topic of the ...
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1answer
50 views
What causes sodium channels to open?
What triggers the opening of sodium channels in a neuronal membrane? Is it acetylcholine that activates sodium channels in the postsynaptic membrane?
Are sodium channels like receptors that have to ...
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2answers
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What makes learning more difficult as we age?
Why is it harder to adapt yourself to different cultures, places, and languages as you age? What makes breaking up with emotional patterns or ideas after years of habit more difficult?
Is there a ...
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1answer
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Do astrocytes connect and chemically communicate with other astrocytes?
I am building a novel model of neural tissue for the purposes of Machine Learning and am currently trying to unpick the functions of the astroglia.
The literature suggests that astrocytes ensheath ...
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A question about how the brain determines the source of a sound
If a person's eardrum vibrates, let's say, 440 times per second for 1 second, how does the brain know its because 1 sound source vibrated 440 times, as opposed to 440 sources vibrating once, one after ...
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Looking for books on How the limbic system works and it role in non-verbal behavior
This is my first post. I just read and I'm currently studying a book called "How everybody works" as a guide to understanding nonverbal behaviors.
After I'm done studying it and while I experiment ...
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28 views
Is there a minimum amount a muscle can move? And thus, gaps in our movement?
Lately I've been thinking about something, based on my knowledge my chain of reasoning works like this...
When you want to move a muscle your brain sends an electrical nervous impulse along the chain ...
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1answer
56 views
What makes synapses stay “fixed”?
What makes synapses not move or pre- and postsynaptic cells neither touch nor move away from each other? I mean the synaptic cleft is a gap between the pre- and postsynaptic cells that is about 20 nm ...
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30 views
can auditory/ocular reflexes exist?
In the same way the knee-jerk reflex is a thing (I think the nerve signal doesn't go through the brain?), can stimuli received by the eyes or ears trigger "instantaneous" (faster than the brain can ...
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Can we “learn” reflexes?
Can we force our bodies to react to situations faster than our brain can think about them?
Some reflexes I can think of off the top of my head:
knee jerk reflex
retracting hand when touching a hot ...
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1answer
42 views
How do we know if a neuron is inhibitory or excitatory?
The textbook examples for an excitatory neurotransmitter is Glutamate, and for an inhibitory neurotransmitter it is GABA.
In my naive understanding, a neuron was inhibitory or excitatory depending on ...
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What makes synaptic vesicle release probabilistic?
The fusion of synaptic vesicles (SVs) with the plasma membrane of the active zone (AZ) upon arrival of an action potential (AP) at the presynaptic compartment is a tightly regulated probabilistic ...
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Could we have endless pleasure?
Are there any studies that point out that we could have a device in the future or drug that could give us endless amount of pleasure by stimulating or blocking processes in the brain or nerve system? ...
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1answer
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What is the basis of the endocochlear potential?
I am learning about the endocochlear potential. According to different sources, the ionic composition of perilymph is about as follows (in mM): 150 Na+, 4-5 K+, 1.2 Ca2+, 1 Mg2+, 120 Cl−, and 20 HCO3−;...
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Does the prefrontal cortex fold over the diencephalon (limbic lobe) during embryogenesis?
The frontal lobe as the top of the vertebrate brain, does it fold over the diencephalon during embryogenesis and development of the brain?
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1answer
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Understanding presynaptic and postsynaptic inhibition
One way to classify neural inhibition is based on the inhibition being "presynaptic" or "postsynaptic".
As far as I understand, the two different types of inhibition refer to the following:
...
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1answer
67 views
What are these two nerves running parallel to the spine called?
I was looking for a human body nervous system, and often times i found a picture like the one below, where there are two nerves running parallel to the spinal column. I searched for it, but nothing ...
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2answers
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Understanding the “Waterfall Illusion”
Motion after-effect illusions, such as the waterfall illusion, refer to illusions where fixating a screen which shows stimuli moving in a particular direction elicits the perception of motion in the ...
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1answer
33 views
Relationship between membrane current and voltage in neurons
Depolarization of neurons leads currents of different magnitudes flow in or out of the cell, and the Sodium and Potassium currents can be separately plotted (Purves):
Caption: Relationship between ...
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1answer
24 views
Changes of permeability and driving force during voltage clamp
An action potential can be understood in terms of voltage changes, and these are fundamentally a function of relative permeability changes, mostly for Sodium and Potassium ions. If for instance the ...
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Is it possible to have action potentials in cells lacking both dendrites and axons?
I'm reading Kandel. Chapter 3 states the following:
Because the initial segment of the axon has the highest density of voltage-sensitive Na+ channels and therefore the lowest threshold for ...
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1answer
60 views
Cerebral/Cerebellar Cortex versus Deep Nuclei
I have troubles using the terms Cortex & Deep Nuclei, and 'Nuclei' in general. From what I understand, a brain has '3 matter types in accordance to anatomical locations'
Superficial Grey matter - ...
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How long does it take the neurotransmitters to diffuse accross the synaptic cleft?
Neurotransmitters get from the pre-synaptic neuron to the receptors on the post-synaptic neuron by diffusion across the gap between these two (the synaptic cleft). My question is, how much time does ...
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Congenital deafness: can cochlear implants always improve hearing at any age?
People with congenital deafness may acquire a cochlear implant at a later age and be able to hear. Given that it seems there is a curve for synaptic plasticity of different circuits:
(1) Cochlear ...
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2answers
97 views
What material fills the synaptic cleft? Is it water?
The synaptic cleft is the gap between the pre-synaptic and post-synaptic neurons, and neurotransmitters are transferred between the neurons within this region. What substance exits in this space, is ...
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1answer
48 views
How do cone cells underneath capillaries receive light?
Came across this image of retina's cross section:
1) How do the cone cells directly underneath the blood vessel ('demarcated in the picture') receive a spectrally correct representation of the ...
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Partial muscle fibre contraction
I'm being taught that: a muscle fibre spans the entire length of the muscle, from the originating tendon to the inserting tendon.
The question is, can a muscle fibre contract only partially? Say, if ...
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1answer
34 views
Is there a maximum testosterone limit, or is it more accurate to say use?
I am constantly amazed at how we cannot differentiate between male and female.
The International Olympic committee sets the target testosterone at 5 nmol per deciliter with active androgen receptors.
...
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Why does an increase in extracellular Sodium concentration increases action potential amplitude?
The title says it - I wonder why an increase in extracellular Sodium (Na+) concentration increases action potential amplitude?
What I understand:
I understand that an influx of positively charged Na+...
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The role of voltage-gated ion channels in chemical synapses
I am trying to understand the mechanisms underlying action potential generation on
the cellular level.
Typically, there is an emphasis on voltage-dependent permeability changes of Potassium (K+) and ...
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0answers
22 views
How are humanized antibodies made?
What kind of antigen is used to provoke/induce an immune response if you are trying to make therapeutic humanized antibodies for cancer and alzheimer's disease?
For example, if you wanted to make an ...
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1answer
54 views
What differentiates neurons in different parts of the brain?
For example: what makes a neuron in the hippocampus of the brain different from a neuron in, say, the amygdala, or the frontal lobe, or anywhere else in the brain? Do neurons in different parts of the ...
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What trajectory do action potentials take, from initial visual stimulus all the way to motor function?
Say we see a mosquito, and our brain tells us 'hey that's a mosquito, you should kill it.' Then we move our hands and slap/clap it.
The initial visual stimulus is translated to an action potential ...
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why do space persons struggle to walk after they returned from space station?
I remember a scene in my childhood (1990s) a cosmonaut was chaired away from a capsule just landed in Kazakhstan (USSR). He lived in space about 200 days.
I guess that he might have lost some ...
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3answers
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Can humans ever directly see a few photons at a time? Can a human see a single photon?
I am not asking the following question: Can humans ever see a photon in the same way we see a chair?
My question is: Can a human retina respond to a single photon? If so, how does this happen and why ...
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1answer
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How important is getting enough glucose for maximal brain performance / cognition?
I know from many studies that have been done, that resting versus active use of the brain has relatively similar overall energy expenditure levels.
On the other hand, however, we know that the brain ...
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Can GENESIS simulation software be adapted to other types of tissues?
GENESIS simulation software http://genesis-sim.org/ is designed for neurobiological systems and it is able to inculude in the simulation the different resolution levels - starting from the molecular ...
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Does loss of dopaminergic neurons totally eliminate voluntary muscular control?
Breathing is a function that is not only autonomic, but can also be temporarily overridden and placed under voluntary control. In fact, you are now breathing manually. Now, suppose that someone has ...
