Questions tagged [neuroscience]

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

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18 views

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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Ion-gated ion channels

Today I've heard for the first time of calcium-gated ion channels but find it hard to get an idea how they work, where they are located, and which role they play. I assume calcium-gated ion channels ...
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Differences between neurotransmitters and neuromodulators

According to the Wikipedia article on neuromodulation a neuromodulator can be conceptualized as a neurotransmitter that is not reabsorbed by the pre-synaptic neuron or broken down into a ...
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To what extent does loss of neurons in the substantia nigra affect movement?

There is a substance known as MPTP that is capable of crossing the blood-brain barrier. Once it does so, it is metabolized into a toxin called MPP+, which then selectively destroys dopaminergic ...
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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 ...
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Parts of the brain pivotal for maintaining consciousness

From an answer to another question (on conscious experiences by coma patients) I have learned that no conscious experiences, complex thoughts, or complex emotions can occur when one is in coma (...
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How does the dopamine spike from drugs compare quantitatively to pleasurable non-drug activities?

I did find this popular press article that quotes a researcher offering the following quantification: "in lab experiments done on animals, sex causes dopamine levels to jump from 100 to 200 units, and ...
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How are presynaptic burst firing signals transmitted post-synaptically?

Neurons can exhibit burst firing and this presynaptic process basically results in a flurry of action potentials being fired in a short time window. I'm, however, wondering how these signals are ...
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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) ...
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How can I apply a PhD in biology without a science academic background? [closed]

I want to apply a PhD in biology related subjects, e.g.: neuroscience, biochemistry... But I don't have a science academic background. What should I do? I have 3 years working experience in ...
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What are the disadvantages of myelin

The myelination of axons has plenty of advantages. It increases signal speed in axons, and thereby reduces reaction times. This is, of course, very good for the survival of the animal in question. ...
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Can acetylcholine leak away from the synapse and cause spasms?

I am currently studying Pharmacology and a question came to mind. We know that Acetylcholine is used as a neurotransmitter in the neuromuscular junction, both Sympathetic as Parasympathetic, but as I ...
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How optimal are the distances of voltage-gated ion channels on axons?

In both myelinated and not-myelinated axon segments ("axons" for short) there are theoretically maximal distances of voltage-gated ion channels beyond which propagation of the action potential would ...
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Number of dopaminergic neurons in VTA

Do you know an authoritative source for the approximate number of dopaminergc cells in the ventral tegmental area (VTA)? Ideally I would like to know this for mice, rats, as well as humans, but one ...
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What is the meaning of depth relation and EM in this excerpt?

In the excerpt below from Morphology of Invertebrate Neurons and Synapses For the better part of a century, conclusions were made largely by matching the depth relations between the terminals of ...
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How does axon guidance system precisely targets specific axons?

Axons find their way to the terminus by responding to axon guidance molecules (AGMs) that attract and repel growth cones or make them stir. This I understand. Through a very specific combination of ...
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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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Vision: what is the difference between on-off ganglion cells and lateral inhibition?

Is 'lateral inhibition' just a term for the biological basis of the functioning of the on-center (or off-center) ganglion cells? Or do these terms describe separate processes?
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Neuron stimulation experiments

Has anyone extracted a class of neurons (or a connected set of neurons) and stimulated them electrically to get an understanding of their behavior? If so, could someone point me to papers along these ...
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Neural circuits and choices

As many know, the brain consists of a circuit made of neurons, which, I think, are interneurons because the brain is a part of the CNS (Central Nervous System). However, are these neurons involved in ...
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Special visceral efferent

Why are special visceral efferent nerves are named as such? They are supplying motor impulses to muscles of pharyngeal arch, which are both skeletal(facial) and visceral(laryngeal) 1, so why only ...
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Are there nerves in the umbilical cord?

I have always imagined that cutting the umbilical cord after birth might be painful. But I have always been confused about who would feel the pain and why. It occurred to me that the mother or the ...
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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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535 views

Does a generator potential pass along a nerve the same way an action potential does?

I have read that a generator potential is a localized depolarization of a membrane. Does that mean that it does not pass along a neuron the same way an action potential does ? If not, then how do ...
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Reward pathway sequence of events

So I've been reading a lot of papers on the reward pathway. But since I'm not schooled in any relevant knowledge I'm having trouble grasping the chain of events. Most papers detail just bits and ...
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How can an animal live without a head / brain?

The human body is unable to do anything if it loses its head - as the brain is separated from the body, the body immediately dies. But why does the same not happen to other species or animals? (As ...
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How is the electrical potential difference distributed between two stimulating electrodes?

Suppose I set the voltage value of an isolated stimulator with a floating ground. I place one electrode above the spinal cord (positive) and the other placed subcutaneously far away from the spinal ...
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Where can I find a diagram of cortex connections?

Has anyone come across a diagram (2D, 3D, maybe even interactive) of the connectiontions between cortex regions? Especially, the diagram should display the strength and direction of those connections (...
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Do ants feel pain?

I have watched video on youtube where guy pours molten aluminium into fire ant colony to make casing. In the comments below there's huge discussion on is that a right thing to do. I am on the side ...
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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. ...
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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 ...
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38 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 ...
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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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Functional unit

What is meant by functional unit of a system? like when we say that the neuron is the basic unit of neural system do we mean that all those things that are performed by neural system can be performed ...
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Does the cranial dura consist of the periosteum? and if not, then is there a mistake in my textbook?

My textbook (Neuroanatomy an illustrated colour text) states that: The spinal dura and much of the cranial dura are separate from the periosteum, which forms the inner lining of the surrounding ...
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Why didn't the human Cerebrum evolve to have granule cells like the Cerebellum does?

The Cerebellum is much smaller compared to the Cerebrum yet it contains more than half of the total neurons contained in the brain. That's mainly due to the granule cells in the Cerebellum which ...
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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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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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what is meta-sympathetic nervous system?

I always knew about the sympathetic and para-sympathetic nervous systems, and today I was told about the meta-sympathetic nervous system, but I didn't understand well the man who told me about it and ...
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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, ...
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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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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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Is there redundancy in the auditory system like there is in the visual system?

In the early visual system, there is a great deal of overlap between retinal ganglion cells, which results in redundancy of the signals that neurons carry to higher visual processing areas in the ...
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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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What is the perisomatic region of a neuron?

In the scholarpedia page on interneurons I encountered the following passage: The perisomatic domain is responsible for the summation of postsynaptic potentials arriving from all dendritic branches ...
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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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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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Are neural connections one-way?

I'm trying to think about how two neurons communicate, typically shown in pictures as an electric pulse traveling along a long, thin connective tissue. Is this depiction somewhat accurate, and if so, ...