Questions tagged [neuroscience]

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

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4
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1answer
77 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?
6
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1answer
237 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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3answers
13k 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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1answer
4k 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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1answer
92 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 ...
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2answers
560 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
468 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
301 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
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1answer
170 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 ...
3
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1answer
796 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 ...
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1answer
164 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
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2answers
606 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 ...
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0answers
106 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 ...
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1answer
4k 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
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1answer
110 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 ...
3
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1answer
343 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?
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2answers
5k 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 ...
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2answers
3k 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 ...
2
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1answer
106 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 ...
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3answers
138 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
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1answer
435 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 ...
4
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1answer
644 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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1answer
5k 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
2k 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 ...
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1k 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 ...
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1answer
2k 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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2answers
679 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 ...
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1answer
76 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 ...
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1answer
141 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 - I'...
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1answer
71 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 ...
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1answer
763 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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12k 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 sections....
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2answers
4k 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 ...
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1answer
719 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
95 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 ...
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1answer
356 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 (...
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1answer
1k 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 ...
2
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1answer
2k 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 ...
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1answer
666 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 ...
13
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1answer
10k views

How does Golgi's neural histological stain work?

What is known about the targets of Golgi staining of neurons? Are larger neurons more likely to be stained? Are specific cell types more susceptible than others? The current wikipedia article says ...
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2answers
105 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
224 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 ...
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1answer
216 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 ...
7
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1answer
308 views

Do adjacent axons in a nerve influence each other?

Suppose I have a nerve fiber consisting of several axons all running in parallel to each other. When an action potential is generated in a certain axon, this will alter the concentration of sodium ...
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1answer
977 views

Why do we feel tired if we sleep excessively?

When we eat, finally we feel full. I know which mechanism causes the sensation of being full. But when we sleep excessively we often still want more sleep. Why does this happen? Is there a mechanism ...
4
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1answer
188 views

What kinds of arousal can a human brain experience?

I've been reading about the new phenomenon called "arousal addiction". The context in which this term is used is Internet, Porn and/or video game addiction(cummulatively Internet Addiction Disorder - ...
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2answers
555 views

Effects of exercise on the brain

I am well aware of the phenomenon of neurogenesis induced by exercise, as well as the dopamine release that results from exercise. I am really interested in neuropsychology and the effects of exercise ...
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2answers
257 views

What is the purpose of the adrenal medulla?

The adrenal medulla is less of a 'real' endocrine organ like the others in the endocrine system and much more an extension of the sympathetic nervous system. In fact, its chromaffin cells are modified ...
3
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1answer
540 views

Neuroscience of temperature regulation and perception

The hypothalamus is known to be important in the regulation of body temperature, but I'm curious whether anyone knows about the neurocircuitry of perceived temperature. It seems like there could be a ...
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3answers
345 views

Action Potential Distribution On Synapses

This is a biology+physics question. Since there is no biology section, I am asking here. In brain, when a neuron reaches to threshold value, it fires an action potential. In most graphics, that is ...