Biology Stack Exchange
Biology Stack Exchange

Questions tagged [brain]

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

Questions should relate to the structure, physiology, and other biological aspects of the brain. Questions on psychology or health are generally off topic.

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Are male and female brains physically different from birth?

Male and female brains are wired differently according to this article: Maps of neural circuitry showed that on average women's brains were highly connected across the left and right hemispheres, in contrast to men's brains, where the connections…
Pablo
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Do animals exhibit handedness (paw-ness?) preference?

I have been observing my cat and found that when confronted with an unknown item, she will always use her front left paw to touch it. This has me wondering if animals exhibit handedness like humans do? (and do I have a left handed cat?) One note of…
Thomas
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Are there organisms with fewer than 1000 neurons?

I'm developing neural networks comprised of just 3 to 10 layers of virtual neurons and I'm curious to know if there are any insect brains out there with fewer than a thousand neurons? Are there any tiny creatures with small numbers of neurons? Do…
J.Todd
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Can brain cells move?

I was discussing this with my brother. I'm pretty sure I read somewhere that they can move. Thanks EDIT: By movement I mean long distance migration (preferably within the brain only).
DLV
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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 cold. It's become better now, but when I had it I…
Lucas
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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 in the speed of transmission of nerve impulses?
lmathl
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Why is the brain white?

I have read many articles about how the brain is the most power-hungry organ in any living complex organism, requiring about 70% of it's oxygen supplies in the resting state. Since the usual medium of oxygen delivery is through respiration, this…
haxkalibrr
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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: There seem to be animals (e.g. hamsters) that can…
user6268
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What's the mechanism for being mentally tired?

I notice that after long tests, or long periods of critical thinking, my body and mind feel noticeably tired. Why does this happen? Are the neurons in my head not firing as quickly, or is there just a perceived lack of mental concentration? What…
Dupontrocks11
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Does human brain store duplicate data?

There are several answers and articles about how the brain stores data, but none specifically cover whether a human's brain stores duplicate data. I was reading in this article that a human brain can have a capacity of 1 terabyte to 2.5 petabytes.…
Johansson
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Supercomputer Vs Human Brain

With supercomputers doing calculation in petaflops ($10^{15}$ Calculations per Second), have we crossed the speed of Human Brain?
Devashish Das
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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 can be asleep while others are awake? In other…
Alex Stone
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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 they and where do they come from? Here is a…
MySky
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The human brain in numbers I: neurons

Even though knowing the number of neurons in a functional unit or with the same function is not of main importance, it may be interesting to know their orders of magnitude, especially in the human brain. For…
Hans-Peter Stricker
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How did the human brain evolve?

A common question posed is, "how did the eye evolve?", because the eye is so complex. However, this has been answered rather clearly and there are several examples around the world of animals in which the eye has evolved independently. The human…
Jez
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