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

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Why are oral cells (or tissues) more heat resistant? [closed]

When we are having meals, such as enjoying hot pot and drinking hot water, we only have a sense of "warm" in our mouth, or even along the organs in alimentary canal. But when we put our fingers into ...
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2answers
61 views

What is synaptic clearance?

Please explain what the term synaptic clearance means. For example, what would dopamine synaptic clearance be? It is important to me in context of dopamine signaling variation due to difference in ...
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1answer
114 views

What is the direction of current flow in myelinated nerve cells?

Is it correct to say electric current flows through the extracellular space, or cytosol of a nerve fiber during impulse conduction? I know that an impulse is actually a change of membrane potential ...
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2answers
87 views

How does valerian make you calmer?

Why do Valerian pills make us calmer? What is the mechanism behind it? I understand how artificial tranquilizers work. Do valerian pill have similar chemical components?
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1answer
175 views

Can the dendrites of sensory neurons be a meter long?

The typical textbook structure of neurons is a cell with a short dendritic tree and a long axon. The dendrites receive information and send it to the axon via the cell body (soma). The axon is a long ...
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1answer
49 views

How are physiological reversal potentials (or ion concentrations) of neurons measured?

Patch clamp electrophysiology experiments typically use an intracellular solution that mimics the ionic concentrations of neuronal cytosol. At the same time, the extracellular solution is meant to ...
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62 views

Why do typical acetylcholinesterase inhibitors (like carbamates) have a greater parasympathetic effect than a sympathetic effect?

I understand that the post-ganglionic neurones of the sympathetic system are adrenergic, but surely these neurones will be excited to the same extent as the parasympathetic post-ganglionic neurones (...
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0answers
32 views

What is an extinction test?

In Stolerman & Olufsen (2001) I read the sentence: After drug-appropriate responding with the training mixtures reached 85%, generalisation to ethanol was examined in extinction tests. ...
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14 views

How do the connections from V1 to V2 form during early development of the human brain?

I am wondering how corticocortical efferents from layer I and II in V1 develop to forward visual information to layer IV in V2. Is there topology preservation in these connections from the beginning ...
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1answer
89 views

What's the explanation for those shivers/shudders that happen at random times? [closed]

They happen at any time, presenting as a sudden urge to shiver/shudder all at once. It originates in the neck and shoulders, feels like instant gooosebumps then out of total reflex shoulders roll back ...
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1answer
17 views

Is the thecal sac ectoderm?

The thecal sac, or dural sac, is the membranous sheath of dura mater that surrounds the spinal cord and the cauda equina. The thecal sac contains the cerebrospinal fluid in which the spinal cord '...
3
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1answer
26 views

How can dopamine modulate synaptic strength?

Does dopamine act on G protein coupled receptor, leading to more Ca2+ channels on the postsynaptic knob? Also, how is the specificity of the location (of the brain) that dopamine acts on controlled? ...
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2answers
140 views

Why we shiver/tremble/shake while performing some work which requires high accuracy?

Shivering when nervous or anxious is a common thing. But, shivering or trembling sometimes also occurs when we are performing a work which requires high accuracy. In such case, our whole body doesn't ...
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62 views

I get regularly get déjà vu - but I know it's not a memory recall - I always think it's from a dream [closed]

My apologies if this is not the right forum for a neuroscientific/psychological question, especially not one coming from personal experience. Please close/move as appropriate :) Doubtless we're all ...
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1answer
56 views

Definition of general anesthesia

To quote Goodman & Gilman : An alternative way of defining the anesthetic state is to consider it as a collection of “component” changes in behavior or perception. The components of the ...
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2answers
81 views

Metabolic activity postmortem

I read some papers about studies on metabolism in post-mortem tissues in human, but I do not exactly the reason about why our brain continues to have activity after death.
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74 views
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1answer
72 views

Do repetitive movements on EEGs show up as discernible patterns?

Here is a typical EEG reading: If I am connected to an EEG, and am sitting perfectly still, and then begin doing some repetitive motion, say, 10,000 times, will we see discernible patterns emerge ...
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86 views

What causes the range of severity of neurological deficits in Down's syndrome?

It's known that the severity of symptoms caused by a trisomy 21 varies from individual to individual. Part of the explanation for this range of severity is the finding that 94% of Down's syndrome ...
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0answers
27 views

Why is the autonomic nervous system divided into parts? [closed]

Why would it be advantageous from an evolutionary perspective to develop parasympathetic and sympathetic systems?
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3answers
95 views

Resting membrane potential: K+ concentrations and charges on inside and outside of the neuron

According to this site, there is a greater concentration of K+ ions inside the cell than outside. The following screenshot, taken from this website, supports this statement. However, I don't ...
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2answers
359 views

Confusion about resting membrane potential and the Na/K pump [duplicate]

To this day, very few people and sources have been able to clear up my confusion about resting membrane potential and how it is maintained. It seems like this is one of those topics that few people ...
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0answers
60 views

What is the reason for fear induced defecation?

I started to handle mice for my job and noticed that they tend to defecate and/or urinate when they are scared. The fear is induced by me, because I need a long time (due to inexperience) to grab the ...
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2answers
169 views

Brain wave and motor movement correlation

I am trying to better understand which brain waves are generated when the motor system (arms, legs, muscles of any kind) are activated. According to Wikipedia, several types (Beta, Gamma, Mu) appear ...
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2answers
83 views

How does the mechanism which controls blood pressure in the brain work? [closed]

I've heard that the blood pressure in the brain is organised by a special mechanism. What is that and how does it work?
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7answers
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Why can't we see in low light if staring long enough?

For me it seems reasonable that if I kept my gaze on a fixed point in a room with low light, a progressively brighter and better picture would appear before my eyes, just like a camera can see in the ...
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1answer
108 views

Synaptic pruning and selective elimination during adolescence

How does Synaptic pruning occur during pre-adolescence, adolescence and post-adolescence, after there is blooming overproduction of synaptic connections until the years of late childhood, and how does ...
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1answer
127 views

All-or-nothing-law: law or general principle?

The all-or-nothing principle indicates that a nerve cell fires at maximum potential or not at all, based on a threshold on the stimulus. Is this a statement which is always true, or only mostly-...
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1answer
77 views

What determines the shape of the center-surround receptive fields of retinal ganglion cells?

The wikipedia article about receptive fields of visual system tells us the following: The receptive field is often identified as the region of the retina where the action of light alters the ...
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1answer
42 views

What kind of changes “stays” in the neuron after the nervous impulse happened?

I often see in neuroscience textbooks about how the brain controls everything in the body with different tracts and etc, and it seems that information is always being transmitted, like there's no ...
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1answer
45 views

What is 'noise'?

In both my psychology, biology and neuroscience classes, professors are constantly talking about 'noise'. For instance, our perception is limited due to 'sensory noise' in our neurons. I am utterly ...
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50 views

How do Binaural Beats Work?

We have a project on different ways of relaxation. One way I found out was binaural beats. Could anyone please tell me how they work. You guys are masters when it comes to simplifying things! All I ...
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1answer
36 views

Are axons capable of endocytosis?

There is evidence for the uptake of toxic substances like prions from the cell bodies of neurons via endocytosis. There is also evidence for prion deposition in white matter. But I haven't been able ...
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1answer
62 views

How difficult is it to make a shRNA/miRNA/siRNA to silence/knockdown NaV1.7 voltage gated sodium channels in humans?

There have been various research projects that experimented with shRNA/miRNA/siRNA to specifically silence/knockdown NaV1.7 voltage gated sodium channels in small animals like rats & guinea pigs. (...
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1answer
52 views

Is HSV-vector-mediated miRNA expression in dorsal root ganglia stable?

My question is on the following article: "Reduction of voltage gated sodium channel protein in DRG by vector mediated miRNA reduces pain in rats with painful diabetic neuropathy" My question is, do ...
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1answer
278 views

Are 2 eyes necessary for 3D vision?

To start off: I'm not a biology student, but a computer science major It has always been my understanding that humans have 2 eyes so that we can have 3D vision: the left eye see more of the left side ...
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1answer
20 views

Are cortical columns restricted to somatosensory cortical sections?

From this previous question, it seems like evidence for the minicolumn organisation of the neocortex seems to be primarily based off observations around the sensory parts of the cortex, such as the ...
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1answer
62 views

Why is stimulation of nerve tissue with a negative pulse called “cathodic” stimulation?

By definition, the cathode is defined as the terminal through which current exits a polarized device. But in the context of neuromodulation, such as spinal cord stimulation, deep brain stimulation, ...
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1answer
43 views

How are individual neuron firing rates characterized?

I'm reading this paper that the Human Brain Project published in Cell and I'm confused how they recorded the firing rates shown in the firing below: In the publication, they mention that they use ...
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1answer
53 views

How does the brain train its neural network?

One question that came up learning how artificial neural networks are working was how the brain can train its neural network? When we say we have an artificial neural network, the problem behind it ...
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57 views

How does a real brain actually learn? [closed]

In biology class we've learned that neurons are connected. If two or more neurons interact with each other often, then the connection gets stronger and stronger, and new connections may form. But if a ...
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0answers
21 views

How are targets formed for axon growth cones (CNS)?

Axons have growth cones which find a route to their target using multiple methods (guidepost cells, attraction to target, etc...). My question is, what is the process that actually forms the target? ...
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2answers
188 views

Understanding the brain: how are neurotransmitters released in the brain?

I have a basic knowledge of how neural networks work. A potential difference is created that forces sodium, potassium, chloride, and calcium ions to flow which carries an electrical signal to the end ...
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2answers
88 views

How can neuronal signals faithfully be reproduced by scalp electrodes?

There is a skull barrier (and possibly other layers too) between the brain and the scalp. I have seen people trying to extract EEG signals from the scalp by connecting electrodes and interface it to ...
2
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0answers
27 views

Synapse formation [closed]

I am trying to learn about neuronal synapse formation, but the literature is intimidating to someone with little background knowledge. I am interested in synapse formation in both human adults as ...
2
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1answer
73 views

Reseach on feeling pain of other people

I'm more of a tech than bio kind of guy, but I have read and learned a lot alongside of my girlfriend's education. Which is very interesting!! Currently I want to investigate : people claiming to ...
5
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1answer
67 views

Does neural network in brain form cycles?

In other words is it possible for dendrite of neuron A to be connected with axon of neuron B and at the same time dendrite of neuron B to be connections with axon of neuron A (or similarly for any ...
2
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1answer
50 views

I know how to solve these equations, but I'm not sure what t' represents?

I am investigating the Wilson Cowan neuron population model, and I can follow most of it, but I'm not sure what is meant by t' in the equation for proportion of neurons in the refractory period. The ...
3
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1answer
67 views

Development and function of spindle neurons

In his book How to Create a Mind author Ray Kurzweil makes some claims about spindle neurons that he provides no source for. Concretely he states that spindle cells: Are Involved in handling ...
2
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1answer
70 views

Dreaming after passing out

I'll have few questions about passing out and dreaming. English is not my native language, and my biology knowledge is very limited. So bear with me. What exactly is blackout? (in a really simple ...