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

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Are there “multi-frequency” signals within a human brain?

I know that neurons can exhibit tonic and phasic firing, and also that a neuron is sometimes called an integrator. This makes me interested to know if there are activities in the brain that depend on ...
4
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0answers
70 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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1answer
135 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 ...
0
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1answer
329 views

How different is an introverts brain different from an extroverts?

How is an introverts brain wired differently than an extroverts? Just to give you an example. On an average, the processing that goes on in an introverts brain is greater than in an extroverts ...
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2answers
8k 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 ...
14
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2answers
309 views

Can parts of a human brain be asleep independently of each other, or vary in the times required for them to fall asleep?

I know that some birds and marine animals can continue complicated activity (swimming, flying?) while one hemisphere of their brain is asleep. I'm interested if human brain has some parts of it that ...
4
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1answer
47 views

Is there a type of amnesia that seperately affects long-term memory?

Is there a medical condition that affects the long term memory, but leaving the short-term and working memories totally or fairly intact?
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1answer
77 views

Eye Brain Mapping

If our eyes are separated by some kind of full proof barrier/isolation, is it possible that our brain can picture/visualize two different pictures at a time? How the brain will function in this ...
4
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1answer
1k views

What part of the brain controls depth perception?

Specifically the part of the brain that does depth perception based on binocular vision. I have searched all over the web and have turned up nothing. Is it the same part of the brain that processes ...
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1answer
2k views

Why do neurons have a negative resting potential?

Neurons expend the majority of their energy powering ion pumps to maintain the chemical gradients that power their electrical activity. To have a negative resting potential, neurons leak potassium ...
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1answer
127 views

Do nerve cells cause action potential in cardiac muscle?

I think the answer is no, but I am not 100% sure. If it was yes, then the dendrite of the nerve cell should each time receive a stimulus causing Na+ channels to open, when the contraction happen. ...
2
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1answer
555 views

Optogenetics - How do microbial opsins work?

I'm just introduced to the optogenetics method and am having some trouble grasping the genetics (of the optogenteics) part of things. So we have Retinal and Opsin that form Rhodopsin molecule that ...
4
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3answers
150 views

What is the difference between different brain regions

The brain is separated into different regions, and different regions perform different tasks. Well, what are the differences between these regions on the cellular/systemic level. The brain is made up ...
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2answers
101 views

Inverse of dopamine reuptake inhibitor?

The wikipedia article on the dopamine transporter gives examples of some drugs whose effects are mediated by the inhibition of the dopamine transporter, such as cocaine and amphetamines. Are there ...
2
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2answers
875 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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0answers
171 views

Does brain activity generate heat gradients in the brain?

I'm reading this article on guiding axon growth using temperature gradient, and it mentions that the trajectory of growth of neuron connections can be influenced by temperature gradients as little as ...
6
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1answer
553 views

Cat purring: What are some possible underlying mechanisms behind purring and bone remodeling and formation?

http://www.scientificamerican.com/article.cfm?id=why-do-cats-purr The article above says that cats purr mostly when they're wounded or under duress. They hypothesis that cats purring leads to ...
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0answers
37 views

Hippocampal regulation of hypothalamus [closed]

What is the difference between CA1-CA4 hippocampal subfields and dentate gyrus (DG) in negative regulation of hypothalamus? I`ve found only evidence that GR expression is more in CA1-2 and DG, while ...
3
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3answers
555 views

Why do neurones use chemical signalling at synaptic junctions?

Problem. When a neurone fires, it sends an electrical signal that jumps down the axon via the nodes of Ranvier very rapidly. At a synaptic junction, chemical brownian diffusion signalling with ...
6
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1answer
496 views

Why does it hurt more when you touch a nerve directly?

I am not a biologist nor know much about biology (so please explain in layman's terms) however I have always been curious as to why this is. What causes the difference in pain between touching an ...
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1answer
51 views

Are there neuronal firing artifacts produced by head movement?

I'm experimenting with a consumer-grade ElectroEncephaloGram (EEG) sensor and have created the image below using the device. Because the sensor on the device does not use a suction cup, there are a ...
5
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2answers
171 views

How does a pinched nerve cause pain (at the molecular level)?

Is this due to pressure differentials in the surrounding tissue? (Is it possible to have a pinched nerve without compression of the surrounding tissues, and does this cause pain?) What are the ...
9
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2answers
2k views

Why is saltatory conduction faster than continuous conduction?

How does spacing apart sodium and potassium channels allow the action potential to travel faster down the axon? This is the reason always cited for saltatory conduction and myelination, but my mental ...
2
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1answer
176 views

Why do I see an inverted image of an object when I close my eyes?

If I stare at an object for a long time and close my eyes, at first I can still see the object with my eyes closed. But the image I see with my eyes closed is inverted: dark colors appear as light and ...
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0answers
198 views

Does sexual arousal inhibit functions of prefrontal cortex in human females as well as males? [closed]

I've read somewhere, that when a human male experiences sexual arousal, his prefrontal cortex and, hence, his ability to reason and make rational decisions, is being heavily inhibited. Sounds pretty ...
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2answers
2k views

What is the function of nodes of Ranvier in axons?

In a neuroscience class I'm taking, it was explained that myelin covers axons in sections, the uncovered sections are called nodes of Ranvier, and signals propagate much faster in the covered ...
2
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1answer
68 views

Carrying or packaging capacity of SAD B19 dG rabies virus

I'm wondering about the carrying capacity also referred to packaging capacity or loading capacity (how many base pairs can be packed efficiently into virions) of the pseudotyped rabies virus SAD-dG as ...
2
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0answers
97 views

How long does Lentivirus take to express in vivo mouse neurons?

Does anyone know how long it takes for a standard Lentivirus vector to express its genes (under a strong promoter such as CAG, CB7, etc.), after injection into the brain of a mouse? By hearsay I ...
2
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1answer
359 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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1answer
143 views

How do axon terminals report to the soma?

It is important to bear in mind that the distance between a neuron's axon terminal and its soma can be extensive, up to about 1m in the human body. The fastest transport along the axon is 400mm/day ...
4
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1answer
702 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 ...
4
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3answers
184 views

Is it technically possible to make someone see something when their eyes are closed?

I'm writing a little article and need any information about how human vision works and latest technologies and discoveries around. Actually its not a professional article. Its for a group of my ...
0
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1answer
278 views

Least painful way to die

There is a lot of talk about inhumane treatment of animals and how we don't kill them in the proper way. I wonder how much research is done on this subject. What is the overall least painful way for ...
6
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3answers
3k views

Why do neurons die so fast without oxygen and nutrients?

Some human tissue can survive without oxygen a couple of minutes, even hours. Why are the neurons are so "weak" and depends so much on oxygen and other nutrients and cannot live without them for ...
4
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1answer
178 views

Zombie Ant Fungus?

Ophiocordyceps unilateralis is a parasitoidal fungus that alters the behavior of the infected. Source: Wiki page. How is the fungus able to alter the behavior of the infected to such specfic ...
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1answer
53 views

Are there any neurotransmitters that trigger all neurons?

I'm reading into the basics of the nervous system, and am intrigued by neurotransmitters. I understand that certain neurotransmitters can trigger more than one neuron type, and may be used as ...
0
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1answer
391 views

Does one neurotransmitter travel all the way through the nervous system?

Nerve impulses of course go really fast, but the neurotransmitters have to travel through millions of nerves, so how can it go that fast? Is it a sort of relay with lots of neurotransmitters taking ...
1
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1answer
1k views

Serotonin - Does being aroused make you sleepy?

My Psychology text book says Serotonin causes "Sleep, arousal levels and emotion" Does this really mean that when you are being aroused, Serotonin is released, which in turn makes you sleepy? If so, ...
0
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1answer
243 views

A good textbook on Neuroscience [closed]

I want to start learning Neuroscience. Can someone give me an advice about a nice textbook for beginners? I'm particularly interested in the application of Neuroscience in programming and AI ...
4
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1answer
265 views

Does frequency of eye blinking reveal anything about human biology/nervous system?

I'm looking at an output of a single dry sensor EEG headband with the sensor positioned above left eye. As a side effect of it's placement, the device picks up eye blinks, and some eye motion as ...
9
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2answers
78 views

Can we disambiguate competing molecular mechanisms of learning and plasticity by measuring electrical activity of neurons?

I have been reading with fascination about the several molecular- and cellular-scale mechanisms and structural changes that underlie what we refer to as long-term plasticity. For instance, [1], [2], ...
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1answer
170 views

What is the biochemical reason for mental fatigue?

Is it known exactly why the brain needs sleep? What's dropping low / going high when we experience mental fatigue? I can see why low glucose could result in mental fatigue, are other reasons known?
9
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1answer
164 views

Systems identification in small neural network

When analyzing data from cortex, we often try to understand what each neuron does in terms of its inputs from other neurons - a specific kind of a systems identification strategy. Most current ...
4
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1answer
108 views

Why do we yawn?

I've read a new study which suggests that yawning may help you keep a cool head. Also, the findings might hold some hope for sufferers of insomnia, migraines, and even epilepsy. Is there any ...
5
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1answer
261 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 ...
3
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1answer
150 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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0answers
24 views

Which Receptors are involved in Psychedelia/Psychosis? [closed]

Which receptors are involved in Psychedelia/Psychosis? I know that the 5-HT2A, 5-HT3, D2, κ-opioid and NMDA receptors are likely involved in psychosis.
4
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1answer
48 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 ...
4
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1answer
310 views

How does the eugeroic modafinil work?

How does the drug, modafinil (Provigil), exert its eugeroic (wakefulness-promoting) effects? I've read that it works by increasing dopamine and histamine concentrations in the CNS and by serving as a ...
4
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1answer
288 views

Why do humans alone have the capability to have religious/spiritual experiences?

What is it in our brain that makes having such experiences possible? I assume other species don't have these. Sure there are instances in the natural world where you can see individuals of the species ...