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

learn more… | top users | synonyms (1)

3
votes
3answers
281 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 ...
3
votes
1answer
276 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 ...
2
votes
3answers
158 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 ...
1
vote
0answers
30 views

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 ...
3
votes
1answer
58 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
votes
1answer
2k 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?
5
votes
1answer
194 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 ...
6
votes
3answers
5k 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 ...
2
votes
1answer
1k 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 ...
3
votes
1answer
398 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 ...
1
vote
1answer
58 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 ...
6
votes
2answers
281 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 ...
1
vote
2answers
151 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 ...
3
votes
3answers
382 views

What exactly is the neural receptive field?

Neural receptive fields map the spatial or temporal distribution of the data to individual neuron excitation, if I understand correctly, but I do not understand if receptive fields (especially in the ...
2
votes
2answers
39 views

What Role Antagonists Play in the Study of Drugs?

I am pretty unfamiliar to pharmacology. I'm doing a research on drug abuse, particularly opioids' mechanism of action. I encountered several times evidences that come from studies using antagonists ...
4
votes
1answer
121 views

What light intensity determines the start/end of a photoperiod in humans?

I'm reading this article, which discusses the influence of Long Photoperiod (LP) and Short Photoperiod (SP) on melatonin production: HIOMT drives the photoperiodic changes in the amplitude of the ...
2
votes
1answer
240 views

What areas of the brain are involved in doing arithmetic operations?

Do neuroscientists already know what areas of the brain are involved in mental calculations? Has any fruitful research been done on that or not yet? Do you think that if we understand what areas of ...
3
votes
1answer
104 views

What triggers creative thought in humans?

Creativity, innovation and ideation. Is there something in the brain that makes the brain think that way, as opposed to "normal baseline". What triggers creative thought in humans?
6
votes
2answers
383 views

If a dead snake reflexively attacks itself, why does it not always attack itself?

Recently there has been this video going around of a snake that had been decapitated. Its body swung around to the decapitated head and the head attacked the body on "reflex". Now we know that most ...
2
votes
0answers
68 views

Does pain scale with mammal mass?

Some biological features scale with the animal mass (see previous Q&A). Assuming the same concentration of nociceptors on the skin surface, I'm wondering how painful a 1 cm wound will be ...
3
votes
1answer
2k views

Neuromediator, Neuromodulator, Neurotransmitter?

Of these three words, perhaps Neurotransmitter is the most obvious. I took a look at Wikipedia page for Neuromodulation and found that this is pretty similar to Neurotransmitter too. I guess ...
2
votes
1answer
73 views

What decides the position of the node of Ranvier?

The oligodendrocytes makes the myelin sheath in CNS and schwann cells make it in PNS. What decides where the oligodendrocyte or Schwann cell will attach and start forming myelin sheath? Is it ...
1
vote
1answer
172 views

Molecules and human memory

Has it been demonstrated that the memory of human brain is just connections between neurons, not "long" molecules such as RNA or proteins?
1
vote
1answer
194 views

If people with colorblindness lack one type of cone cells, shouldn't they be unable to recognize one particular color?

The 3 types of cone cells in normal humans allow them to view 3 types of colors and any color made from mixing and matching those 3. So, 2 types of cone cells should only allow to view just 2 types ...
2
votes
2answers
2k views

What is a cortical circuit?

I have read about cortical circuits in the context of connectomics (e.g. any example here) and computational neuroscience (e.g. any example here), but a simple Google/Wikipedia does search not show an ...
1
vote
1answer
430 views

Is Nerve Growth Factor (NGF) commercially available?

I'm curious if NGF, or Neurotrophins in general is available commercially. Can I order it online? If not, what are the medical/biological reasons. Does it breakdown quickly after synthesis/capture? Is ...
4
votes
1answer
48 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?
3
votes
2answers
1k views

Physiological indicators of happiness and well being

If I understand it correctly, levels of serotonin in the brain can indicate if a person is happy. What other physiological measures indicate happiness or well being for a humans? I am looking for ...
1
vote
1answer
81 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 ...
5
votes
1answer
155 views

Is (Brain Mass)/(Total Mass) still considered a valid indicator of intelligence?

I was reading this(1) and it led me back to ask a very basic question (I'm not a neuroscientist). All the way back to undergrad anthropology and neuroscience courses I remember being taught the ...
1
vote
3answers
100 views

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 ...
3
votes
1answer
212 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 ...
2
votes
1answer
424 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 ...
6
votes
1answer
3k 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 ...
5
votes
1answer
2k 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 ...
4
votes
3answers
1k 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 ...
1
vote
1answer
163 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. ...
3
votes
1answer
946 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 ...
2
votes
0answers
479 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
votes
1answer
1k 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 ...
7
votes
2answers
273 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 ...
1
vote
1answer
60 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 ...
9
votes
1answer
111 views

Which brain regions are D1 dopamine receptors expressed, and which brain regions are D2 dopamine receptors expressed?

This is a follow-up question to If D1 receptors stimulate adenylate cyclase (through GPCRs) and D2 receptors inhibit it, then why do mutations in both have similar effects?. As a further question - ...
4
votes
1answer
57 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 ...
2
votes
1answer
277 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 ...
5
votes
2answers
4k 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 ...
10
votes
2answers
2k views

What is Peter's rule in neuroscience?

I have heard and read about Peter's rule informally in the past, but never saw a formal definition or description. Informally I have learned to understand Peter's rule as the assumed correlation ...
2
votes
0answers
143 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 ...
3
votes
1answer
491 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 ...
1
vote
1answer
63 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 ...