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

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What is a inhibitory tone when talking about neurons?

In this SE answer: Could an "overactive" brain increase the chances of Alzheimer's Disease? user @nico used the word inhibitory tone What does that ...
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Why does getting certain chemicals in cuts hurt?

More specifically, shampoo. What are the mechanics of detecting a noxious chemical stimulus in terms of which receptors recognise what, how do they do it, and how is this information relayed to the ...
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Long-term-potentiation and memory. Where do we stand?

I was reading the answers to the question: How and where, in the human brain, are memories stored? and, as expected, LTP and LTD came out. Every time I read about LTP/LTD there is always something ...
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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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358 views

What are the “stars” we see after a bump on the head?

Sorry if this might appear funny. When I close my eyes for a longer time, and suddenly open it, I see some twinkling white small circles, and when i concentrate on anyone of them it disappears, as ...
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What would be the conduction speed of A-alpha fibers, were they unmyelinated?

It's known (Hursh 1939) that myelinated axons exhibit the behavior $v = 6d$, where $v$ is the propagation speed [m/s] and $d$ is the axon diameter [μm]. A related relation for unmyelinated axons is ...
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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 - ...
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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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288 views

Why do we like music?

Music is, of course, just a sequence of sounds. Sounds are vibrations in the air, which our ears detect. So why do we find certain sequences of sounds to be appealing? What makes us want to hear these ...
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169 views

How reversible is DAT upregulation from long-term ADHD medication use?

A mechanism for ADHD stimulant medication tolerance has now been found. See http://neurosciencenews.com/adhd-medication-patient-brains-adapt-dat/. Here's the thing though: what exactly is the ...
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Do memories have mass?

If it were possible to live forever, would our brains grow infinitely with the number of memories that we store? Or would we remove old memories as we create new ones?
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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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Why can't neurons undergo cell division?

Many cells in the human body can divide and reproduce, making healing possible. Neurons, however, cannot reproduce, which makes diseases affecting the brain particularly crippling. Why can't neurons ...
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Why are potassium channels slower than sodium channels?

I am relatively new in the subject of biology. I have a strong mathematical background and in order to get into the field of computational neuroscience, I am trying to get some biological background. ...
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116 views

Are Schwann cells the sole source of myelination in PNS?

Are Schwann cells the only source of myelin for axons in the peripheral nervous system, or are there other neuroglia or other processes that result in myelination of PNS axons?
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Can people with paralyzed eye muscles see?

As far as I am aware, the saccades of the eye are central to visual perception. If the eye is held still, the human stops seeing, even if light is reaching the retina and the visual pathway is intact. ...
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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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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 ...
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Is the squid giant axon the fastest conducting unmyelinated axon known?

The conduction velocity of the squid giant axon can reach 30 m/s. Is there any known example of an even faster conducting unmyelinated axons?
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Can we change our dopamine baseline levels?

Can we change our dopamine baseline levels? High dopamine levels improve alertness, problem solving, but may also cause anxiety and aggression. I've read that smiling and laughing, eating certain ...
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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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Is there a biophysical causation from local field potential (LFP) to spikes?

Many experiments showed that neurons tend to fire at some phase (usually trough) of local field potential (LFP) oscillations, such as theta or gamma rhythm. LFP is supposedly generated by a population ...
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Do we use 100% of our cerebral capacity?

I saw a movie yesterday called Lucy. In this movie, a girl called Lucy absorbs a large amount of CPH4, and her brain capacity slowly increases. So that brings me to my question which is : Do we ...
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How does an inhibitory synapse communicate to the cell body of a neuron?

I picture a neuron as having multiple trees of dendrites attached to the cell body with a single axon leaving the cell body. I believe the cell body near the axon root makes the decision to fire or ...
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Is there any way a human could whistle and be unable to speak?

Is there any situation anatomically, where a human could understand the speech of others perfectly, without any capabilities of speech themselves, but would retain the ability to whistle with a tune? ...
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Are unilaterally deaf people able to determine where sound comes from?

My question is on people deafened in one ear, but normal hearing in the other. Time and level differences between the two ears are only part of how the human body can localize the source of the ...
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What is the mechanism behind tinnitus?

I seem to have come across two contrasting explanations for tinnitus induced by loud noises- i.e. damage to the hair cells in the cochlea. On the one hand, I have read that damage to the hair cells ...
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Single long axon vs serial neurons

Based on the comments in this post and also this chat. For discussions and speculations please comment in the chat. The basic question is what is the advantage of having a single long axon such as ...
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Why are melodies/harmonies perceived as pleasurable by humans?

Is there any evolutionary advantage to finding melodies or harmonies pleasurable? Does the ear pick up these particular oscillating waves differently from other sounds, and if so, how does that affect ...
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Soma-soma paired neurons

I'm reading this paper about how neurons can connect. Wikipedia says, typically neurons connect via axon (transmitter) and dendrites (receiver) but there are also special cases where dendrites connect ...
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Is it possible for a human to wake up in a wrong way?

There's an old folk saying that goes like "He got out of bed on a wrong foot" - to indicate that the person's day is going poorly because of the way that person woke up. Is it is possible for a human ...
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If my brain lost all of its activity for a moment, would my memory be gone too?

I can't remember which question it was, but in the past here, it was explained to me that memory is actively stored in the brain, rather than "physically". Meaning, memories are made up of the brain's ...
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604 views

How does the brain avoid feedback loops?

The article Ants Swarm Like Brains Think really helped me to understand the way that neurons which are pretty dumb on their own (like ants) can work together to create a pretty genius system (a brain ...
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What processes are responsible for focusing on an image only seen by one of the eyes?

When a person is spying from around a corner with only one eye, it's rather easy to ignore the other eye's image, since it's probably much darker, because one usually spies around a corner standing ...
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Original paper about the all or none law for neurons

I am looking for the original paper about the all or none law for neural activity. I know that there is a very old article about the all or none law for mammalian heart muscle fibers, but I'm ...
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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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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 ...
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How well does it actually work to surgically reroute the optical nerve?

Two publications, Roe et al, 1992[1] and Metin & Frost, 1989[2], describe results pertaining to the ability of a region of cortex to process information from a different sensory mode than the one ...
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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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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 ...
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What alternatives are there to the amyloid hypothesis?

Given the recent failure of the Bapi clinical trial, there is a lot of questions that have arised from he amyloid hypothesis. However, I can't really think of many other mechanisms that don't involved ...
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Why does the human brain not overfit when training at some task?

One of the problems that occur during (artificial) neural network training is called overfitting. The error on the training set is driven to a very small value, but when new data is presented to ...
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Why has evolution made neurons use spiking?

I'm going to be forward and say that I'm not a biologist. I don't claim to fully understand the functionality of a neuron from an electrical/chemical perspective... I'm curiously gazing from the ...
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Is warmth/temperature sensed linearly or on a different scale?

I understand that the atmospheric temperature is sensed relative to external body temperature. However, is the sensation of warmth registered linearly, or is it on a logarithmic scale, similar to ...
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Dark veil when getting up too fast

I was asking myself this weird question. When you get up or stand up too fast, sometimes, you see something like a dark veil, and you aren't able to see anything distinctly for 2 or 3 seconds, then ...
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Lumosity.com? Is it based on science?

I always see these Lumosity adds on TV, and I personally feel they are just trying to "sell me something". I did some layman's research(wikipedia) and read that "Studies of Lumosity's effectiveness ...
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Is there a correlation between total neurons and intelligence?

Thanks for looking. First off, I am not a biologist, just a curious layman, so I apologize in advance if this isn't a "good" question. Please don't downvote me into oblivion. I read today that the ...
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102 views

Neuronal Architecture of the Brain

To what extent do brains (e.g. of humans) contain recurrent connections? I am studying artificial neuronal networks and frequently encountered the statement, that recurrent neural networks are ...
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How is color information transmitted from the eye to the brain?

Is color information sent from the eye to the brain frequency-modulated, or are different colors transmitted by different axons? I know that each ganglion cell is connected to multiple ...
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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 ...