The primary component of the central nervous system, which, along with the spinal cord, controls the body of bilaterally symmetrical beings.

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3answers
32k views

If the brain has no pain receptors, how come you can get a headache?

I've read many years ago in books, that the brain has no nerves on it, and if someone was touching your brain, you couldn't feel a thing. Just two days before now, I had a very bad migraine, due to a ...
19
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5answers
6k views

Why do the two hemispheres of the brain control the opposite sides of the body?

Why does the left hemisphere control the right and the right hemisphere control the left? I googled it but didn't find a good answer regarding this. Could someone explain? Does this adaptation help ...
15
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2answers
393 views

Can parts of a human brain be asleep independently of each other, or vary in the times required for them to fall asleep?

I know that some birds and marine animals can continue complicated activity (swimming, flying?) while one hemisphere of their brain is asleep. I'm interested if human brain has some parts of it that ...
14
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3answers
4k views

Supercomputer Vs Human Brain

With supercomputers doing calculation in petaflops ($10^{15}$ Calculations per Second), have we crossed the speed of Human Brain?
12
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2answers
226 views

How does an axon “know” it's not connecting to its own neuron?

I recently read about an experiment where they removed the dendrites and axons from rat neurons and placed them on a grid. After a while they started reconnecting and were able to learn things. Since ...
11
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1answer
343 views

Is there a significant difference in sedentary calorie-burn between a thinker and non-thinker?

I've read that, on average, a sedentary female burns between 1,600 - 2,000 calories and a sedentary male burns between 2,000 and 2,500 calories. I've also read that the brain itself burns quite a few ...
10
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2answers
760 views

What happens once a brain is full?

I just read the answer to this question, and it got me thinking... If the human brain (or any other brain) has a finite amount of storage, what would happen once the brain has taken in its maximum ...
10
votes
2answers
454 views

Why does strenous exercise cause vision of “lights”?

I had a hard climb a week ago. I got so tired then any time I closed my eyes I saw these lights inside my head. I see these lights almost every time that I run fast or some thing like that. What are ...
9
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1answer
515 views

Why does this illusion work?

This is another image I found on Google+ All lines are absolutely straight, parallel and perpendicular but why does it appear to have a curvature? Related: How does this illusion work?
9
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3answers
633 views

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?
9
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1answer
1k views

How does this illusion work?

I found this image on Google+ If you shake your head you can see a portrait of a person. Can anyone explain how the image is constructed in the brain?
9
votes
1answer
480 views

Is it possible to lose synapses over time?

I mean, what if a person is for a long time submitted to conditions in which his mental capacities are not explored, are the synapses undone? I've heard that drugs may cause such an effect, but what ...
9
votes
2answers
104 views

Is mammalian vision processed as a sequence of frames?

I often read that people believe that human vision has an inherent frames-per-second rate (FPS) that causes stroboscopic effects - such as seeing the spokes of a rotating wheel apparently rotating at ...
9
votes
3answers
153 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?
9
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2answers
1k views

How long does it take for memory to disperse after death?

1: There seem to be cases where coma patients with a non-active brain (i.e. flat EEG) have regained full consciousness. => Apparently memory and knowledge are stored independent of brain activity. 2: ...
8
votes
1answer
126 views

What happens when we know that there is something that we forgot but we can't remember what it was?

I think it happens for everyone that sometimes we go to a room and forget why we went there. Is there any research or article on this?
8
votes
1answer
223 views

Is it a limitation of the eyes, or the brain, that we can't see a moving bullet?

Are the photoreceptors in our eyes not fast enough to register the fast moving bullet, or is the brain not powerful enough to make sense of something happening that fast?
8
votes
1answer
1k views

Disadvantages of unihemispheric sleep

Is is well known fact that marine mammals and some birds can sleep with one brain hemisphere at a time, since it's essential for their survival. However, at least in my opinion, such mechanism would ...
8
votes
2answers
159 views

Does Lucid Dreaming decrease the regenerative effect of sleep?

After watching this SciShow video on sleep, I wonder about lucid dreaming. Specifically: Does lucid dreaming and associated directed agency within Lucid Dreaming decrease the regenerative effect of ...
7
votes
1answer
2k views

Can a human acquire a memory of an animal? [closed]

I would like to know if it's possible for a human to acquire an animal memory. I mean, animals store their memories in their brain, right? And so do we, humans, store our memory. So, is it possible ...
7
votes
3answers
262 views

Can the human brain be reduced to a binary system?

Does the brain really function like a computer as in, ultimately every response is related to a binary sequence based on whether particular neurons fire or not?
7
votes
4answers
713 views

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 ...
7
votes
1answer
99 views

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 ...
7
votes
2answers
135 views

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 ...
7
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2answers
1k views

How are babies born without a brain?

In the United States, anencephaly occurs in about 1 out of every 10,000 births. There are several forms of this condition, wherein the forebrain is absent. The forebrain is host to most of the higher ...
7
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2answers
117 views

Why did the Brain develop in the front in most organisms?

I was wondering: why most, well, pretty much all organism with a brain have it right in front of their bodies or at the top.
6
votes
1answer
386 views

Influence of alcohol on brain cells

As I am not related to biology, I would appreciate if you can keep your answers as simple as possible. My question is about the influence of alcohol on the brain. As far as I know, drinking alcohol ...
6
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2answers
56 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 ...
6
votes
3answers
185 views

Why are males more likely than females to have autism spectrum disorder?

The male to female ratio in autism spectrum disorder is around 4:1. However it seems ASD is not a simple X-linked disorder. Then how is it possible males are more susceptible than females, if the ...
6
votes
2answers
202 views

How would the human body adjust to sleep times if we were to live in a place with different day lengths?

You sleep at night and are active during the day that's how things work for humans, but theoretically if a human whose parents lived on earth were to be born in another planet resembling earth but the ...
6
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1answer
128 views

How much total RNA can be extracted from Drosophila brain

I am wondering how much total RNA could be extracted from a single D. melanogaster brain. I could not find this information from the literature. The closest hit was this paper, that claims that ...
6
votes
1answer
94 views

How well do we notice asynchronicity?

I'm stopped at a stoplight and, with nothing to do, my thoughts wander to the timed don't-walk sign that governs any pedestrians who might wish to cross the street I'm driving along. I can see two ...
6
votes
1answer
61 views

How does the frequency of a visual stimulus affect the steady-state visually evoked potential?

I want to design a project for EEG signal processing. In my research I found the concept of SSVEP. SSVEPs represent the electrical activity of the brain as measured via EEG, and are evoked by visual ...
6
votes
1answer
240 views

What is meant by “neurotransmitters flooding the brain”?

I frequently hear expressions like "Dopamine flooding the brain" or "X neurotransmitter flooding the brain" used to communicate with general audiences. For example: "Following [orgasm]? oxytocin ...
5
votes
1answer
386 views

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 ...
5
votes
4answers
236 views

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 ...
5
votes
3answers
207 views

Can children restore brain cells?

By "children" I mean young people at the age of 10 or lower. I know that the adult brain cannot restore brain cells, but what about children? I mean, the brain must develop from a few cells to a 90 ...
5
votes
1answer
43 views

How does de-myelination occur in multiple sclerosis?

From what I understand, only the oligodendrocytes are affected in multiple sclerosis, and they are attacked by T cells which cross the blood-brain barrier. This leads me to two questions: How is the ...
5
votes
1answer
67 views

Do human neurons in a petri dish do different things from chimpanzee neurons

I want to know if qualitative experiments have been done growing chimpanzee neurons and human neurons in vitro and have any differences emerged, such as the amount of connections per neuron or ...
5
votes
1answer
81 views

Can the negative afterimage appear only if there is light or is it possible in darkness?

Reading the following paragraph: After staring at the red and blue shamrock, you saw a green and yellow afterimage. Opponent-process theory proposes that as you stared at the red and blue ...
5
votes
1answer
107 views

How does the brain cool itself?

Thoughout life everyone tells you that brain is essentially a computer but just like computers your brain would create immense amounts of heat by being in use, so if that's the case how does it cool ...
4
votes
1answer
98 views

What are the total number of action potentials in the human brain?

Is there an approximate figure of the total number of action potentials in the human brain? It's my understanding that there are ~ 60 billion neurons in the brain with ~ 100 trillion connections ...
4
votes
2answers
134 views

What is the biological principle of this “holotropic breathwork” technique?

Holotropic breathwork is a non-drug technique developed by Stanislav Grof used in psychotherapy. The therapy as a whole is usually called holotropic breathwork (at least by Grof himself) and will most ...
4
votes
1answer
509 views

Is there any size limit to the amount of information a human (or other) brain can hold

Im not sure how this would ever be tested but is there a limit to how much the brain can 'hold' before it reaches capacity ? I guess this could also be interpreted in terms of memory, as how well ...
4
votes
3answers
178 views

What is the difference between different brain regions

The brain is separated into different regions, and different regions perform different tasks. Well, what are the differences between these regions on the cellular/systemic level. The brain is made up ...
4
votes
1answer
41 views

Is the autonomic nervous system only activated by internal stimuli?

My professor claims that the autonomic nervous system is only activated by stimuli from organs but I really feel like I've read that it can be activated by outside stimuli, although I'm not sure what ...
4
votes
1answer
52 views

Oxygenated hemoglobin in MRI

I have read the following sentence: Because this oxygenated hemoglobin is unaffected by magnetic fields, the response RF signal returned to the fMRI scanner is stronger when there is more ...
4
votes
1answer
90 views

How could be the “Eurasian magpie” bird won the “Mirror Test” where Gorillas failed

EURASIAN MAGPIE VS GORILLA VS How could be the "Eurasian magpie" bird won the "Mirror Test" where Gorillas failed ? In 1982, mirror tests on two, zoo-reared gorillas failed to demonstrate ...
4
votes
1answer
94 views

How Behind is the Human Mind (Latency of the Senses)

I would like to know if there is any research into the latency of human perception. Particulary: What is the minimum time for various inputs (vision, touch, sound) to be recognized by the conscious ...
4
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1answer
2k views

What are the advantages and disadvantages of being ambidextrous?

What are the advantages and disadvantages of being ambidextrous? We have two hands and we nearly can't use one and this seems like a weakness, and a stupid one when you first think about it. But ...