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

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Neuroendocrinal mechanism of parturition

My book reads, "The fetus signals that it is mature by secreting certain hormones that diffuse across the placenta into mother's blood and cause the secretion of oxytocin from her posterior ...
2
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0answers
106 views

Saltatory Conduction Of Nerve Impulses

I am aware about some basics of Saltatory conduction of nerve impulses. I know that the nerve impulses(ionic flow and the depolarization) are transferred from the node to the node in myelinated nerve ...
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1answer
37 views

Do local field potentials (LFP) create waves on the surfaces of nerve cells?

Are waves created by the LFP on the surfaces of neurons cell bodies? Since the cells have a resting potential, do these waves create harmonic oscillation of the membranes at particular frequencies? ...
2
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0answers
20 views

What features cause mechano sensory adaptation?

In relation to mechanoreceptors (e.g. pacinian corpuscles), what stops a constant stimulus from producing action potentials? I understand that adaption is used to filter out stimuli that aren't ...
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1answer
212 views

What is the physiological difference between snorting/swallowing cocaine

I know that mucosa inside the nose absorbs cocaine molecules when snorting cocaine, but what difference is there compared to swallowing? Also more cocaine administration equals more cocaine molecules ...
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0answers
32 views

Alpha wave frequency variance in EEG of single subject over period of a few hours?

I have an Emotiv EPOC (EEG headset: 128 SPS, notch filter @60 Hz, felt saline contacts) I've been playing around with. Over the course of two or three hours using CCA to plot an SNR contour against ...
3
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0answers
103 views

How is membrane capacitance related to the increased speed of saltatory conduction?

Here is the original question which inspired my question below. As explained by the answers there, the reason saltatory conduction in myelinated neurons is faster than non-myelinated conduction is ...
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1answer
139 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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21 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 ...
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1answer
154 views

Are inflammation and anxiety connected?

I've been reading a curious paper about the use of cannabis, and one of the passages piqued my interest: There’s also been a lot of work done on another constituent of marijuana, cannabinoid, ...
3
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1answer
60 views

Confused at what is happening with these action potentials

Ok so for a bit of a background, I am doing a science project looking at the action potentials of the earthworm. I anaesthatized the worms then hooked them up to a spiker box ...
4
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1answer
53 views

Missing cells from immunopanning

Why do I not have any cells left in my positive panning plate after transferring from the negative panning plate during immunopanning? I am trying to purify retinal ganglion cells from postnatal rats ...
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2answers
4k 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 ...
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2answers
72 views

Epinephrine vs. Adrenaline

Both names are widely used, with what appears to me as a slight prevalence of “epinephrine” in scientific literature and an overwhelming prevalence of “adrenaline” in popular media. Are there any ...
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0answers
62 views

Organisms with the most extreme sensory capabilities? (sight, smell, sound) [closed]

Background It is quite mind boggling to imagine what it would be like to be missing sight, sound, touch, smell, taste etc. Question Which organism holds the record for most extreme sensory ...
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1answer
137 views

Is there a maximum pain threshold?

Is there a maximum threshold of pain a Human can experience, beyond which point there is no noticeable difference? I ask this question in part to better understand the definition of pain and its ...
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2answers
1k views

Do neurons secrete multiple neurotransmitters, or just one type?

I know that neurons communicate between each other by filling the junction between dendrites with neurotransmitters. What interests me is if a single neuron only works with one type of ...
3
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1answer
163 views

Are there any types of cancer that cause neurons to divide?

After birth neurons generally do not divide. But is there any specific type of rare cancer or tumour where neurons divide? And if there is such a cancer, then how is it possible for a neuron to regain ...
34
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4answers
7k views

How does the brain's energy consumption depend on mental activity?

What is the impact of mental activity on the energy consumption of the human brain? I am most interested in intellectually demanding tasks (e.g., chess matches, solving a puzzle, taking a difficult ...
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9answers
7k views

Why have humans evolved much more quickly than other animals?

Humans have, in a relatively short amount of time, evolved from apes on the African plains to upright brainiacs with nukes, computers, and space travel. Meanwhile, a lion is still a lion and a ...
3
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0answers
57 views

The Operation of tuning in the S1 layer of ventral model

According to my previous question in ventral Stream pathway and architecture, I want now to get a brief example about how the S1 layer is constructed. In other words, how all the simple units are ...
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1answer
63 views

What will happen if we expose the brain to an intermittent light?

If a brain is exposed to an intermittent light are specific areas going to fire? If yes, which of them? Is there any experiment about this?
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0answers
66 views

Why are there different types of neurotransmitters?

Why does the type of neurotransmitter matter? If the neurotransmitter just stimulates a dendrite on a neuron which causes electricity to move through via sodium-pottasium pumps and ion gates to ...
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1answer
63 views

What in neurons and their connections changes during the process of learning?

I'm not sure if this question belongs more in physics or biology (or maybe even computer science)... but biology seemed to fit more. What changes in the state of our brains when we learn things? ...
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2answers
1k views

Why do neurones have only one axon?

I have just learnt about neurones. I wonder why neurones have only one axon. Can they transmit nerve impulses faster and more rapidly when they have more axons? Does having more axons help in ...
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1answer
59 views

Radial Basis Function Network (RBF Network)

In the Wikipedia article on radial basis function network, I didn't understand what was meant by "center vector for neuron i", in other words "center of the RBF units called also prototype".
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1answer
165 views

Understanding Membrane / Resting Potential from the perspective of ions?

From wikipedia article RESTING potential: "there is no actual measurable charge excess in either side. That occurs because the effect of charge on electrochemical potential is hugely greater than ...
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2answers
395 views

How is temperature sensed?

Can anyone summarize the mechanism by which when an object of a given temperature is placed in contact with, say, the skin on a human fingertip, the average speed of the particles of the object is ...
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0answers
41 views

Nocioception (pain perception) in subcutaneous tissue

There seem to be no nocioceptors (pain and temperature sensitive nerve endings) in subcutaneous fat. there are nocioceptors and other receptors in veins running through fat, but these can be avoided. ...
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3answers
161 views

Mechanical cause of loss of consciousness

Consciousness is an electrical and chemical interaction in the brain, caused by neurons firing and chemical interactions. How does a mechanical "force" cause this to stop working? i.e. How does a ...
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0answers
83 views

Learning first-year biology + anatomy via documentary? [on hold]

Probably going to take first-year biology in ~4 months; so was thinking to go through MIT's 7.00x on EdX… However seeing at how popular this topic is, I was thinking there might be a fun documentary ...
3
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1answer
159 views

Ventral stream pathway and architecture proposed by Poggio's group

Please can you give me a very brief explanation about all functions in the ventral stream architecture summarized in this figure: This figure is from Serre et al.'s A quantitative theory of ...
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3answers
125 views

Why are things conscious?

I've been referred to here from http://philosophy.stackexchange.com/questions/8052/why-are-things-conscious. Could you guys help out? Here's the question: What is the reason for animals or more ...
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0answers
71 views

Unexplained pain in the legs at night, possibly due to peripheral nerves - diagnosis and cure? [closed]

I have seen a few instances where people suffer from tremendous pain the legs, often around the region of ankle, going a bit down and stretching up to knee. This happens most prominently at the night ...
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1answer
8k views

How reversible is decerebrate posturing caused by brain stem damage?

This is a follow-up question to How likely would Abraham Lincoln be to survive his wounds today? You don't have to see a CT scan or autopsy to know if the brainstem is injured (directly or ...
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How is saltatory conduction faster than conduction of unmyelinated fibers? [duplicate]

It's always the same explanation that currents are able to "hop" along Ranvier nodes instead of passing continuously along the axon making saltatory conduction more efficient than continuous ...
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1answer
52 views

Number of MHCs in neurons

I have read that neurons have proportionately less MHC molecules than other cells of the body. What is the advantage of this?
3
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1answer
164 views

What happens in your brain when you receive information which causes you to bristle?

I'm talking about moments when you watch a film and you bristle, or when you listen to music, etc. What kind of neurotransmitter flow changes?
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1answer
173 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 ...
2
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1answer
124 views

What happens in the synapse when cocaine administration occurs in the human brain

As far as i know when you accept cocaine in your blood some cocaine molecules reach some synapses in your brain and fill some Reuptake tunnels preventing the cell to simply "do not know that fired ...
3
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1answer
474 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 ...
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3answers
2k 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 ...
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2answers
1k 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 ...
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1answer
175 views

What is 'calcium conductance'?

What is the meaning of calcium conductance in ion channels. I encountered this in the following text: It was established that the µ and δ opioid receptors open potassium channels, which results ...
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2answers
88 views

Which part of the brain needs to be shut down to lose conciousness?

Whether it is mechanical (trauma), chemical (anaesthesia) or electrical - which part of the brain is shut down to cause loss of consciousness?
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1answer
122 views

L1 - L5 layers of the brain

I have read in some papers about the layers L1-L5 of the brain (e.g. in this paper). I could not find a definition of these layers. I have found information about the layers V1-V5 in the visual ...
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1answer
49 views

Does sympathetic nervous system acts bilaterally for pupil dilation or other two sided organs?

The question might seem weird. Does sympathetic nervous system acts 'bilaterally' meaning if you shout to a person's left ear a loud noise (e.g. by headphones), will it activate sympathetic system ...
3
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0answers
60 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 ...
5
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2answers
156 views

Why do the brains of cocaine-users shrink faster than the brains of non-cocaine users?

http://news.sciencemag.org/sciencenow/2012/04/cocaine-may-age-the-brain.html?rss=1 Cocaine-dependent individuals showed a significantly greater-than-normal age-related decline in gray matter in ...
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2answers
92 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 ...