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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Which hormones can cross the blood brain barrier?

Can hormones such as testosterone, aldosterone and estrogen cross the blood brain barrier? I looked on Wikipedia and there no mention of it in the testosterone article. Through Googling around I also ...
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157 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 ...
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685 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 ...
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40 views

What physical or mental actions can be picked up by EEGs?

There certainly seem to be a lot of gadgets and gizmos leveraging EEG technologies to the control of devices. This makes me wonder: what intentions/thoughts can be captured by EEG technology, and ...
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74 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 ...
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157 views

Case study and speculations on the brain of Edward Mordake

I am very interested in the case of the man named Edward Mordake who lived in the 19th century. In particular, he had two faces. If you have not heard of this man, please, search this up as there are ...
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87 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 ...
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113 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 ...
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697 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 ...
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125 views

Headshot = instant kill? [closed]

While whatching a film, I've been thinking about how does a headshot kill someone, and how long does it take? For example let's say you've beeing shot by a normal (police) handfired weapon - no ...
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127 views

How small does a nanobot have to be to “swim through the brain” and access any neuron it wants to?

I read on this question What is in the space between neurons in a brain? that there is actually not much empty space in a brain. But my question is slightly different. Is there a visual demonstration ...
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130 views

How do ascending neural pathways filter unimportant information?

In school they told us one of the functions of the ascending neural pathways is to filter unimportant information. But the neural signal I know, is only a chemical-electrical chain of neurons. Is this ...
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268 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 ...
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197 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 ...
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1answer
15 views

“Next generation” brain scanners, can they detect CTE?

I've just read the news that a "new generation" brain scanner is under development. I wonder whether they can detect chronic traumatic encephalopathy. I haven't been able to find the paper about these ...
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1answer
120 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 ...
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187 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 ...
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208 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 ...
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193 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 ...
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2k views

What is the average volume of the hippocampus?

I'm trying to find any information on sizes of the hippocampus? Ideally in the average adult male & female brain
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721 views

How does toluene inhalation damage the brain?

We just had a discussion about toluene abuse. It is known, that people inhaling toluene for a long time have significant brain damage, including decreased intelligence. I found that toluene is a ...
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1answer
44 views

How long does a spiking signal last?

It is surprisingly hard to find information about the timing of neurons, in particular how long an action potential can contribute to the summation of a neuron. Is it on the order of milliseconds or ...
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144 views

Brain wave and motor movement correlation

I am trying to better understand which brain waves are generated when the motor system (arms, legs, muscles of any kind) are activated. According to Wikipedia, several types (Beta, Gamma, Mu) appear ...
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1answer
47 views

Why does our mouth “water”?

Whenever we see something delicious, rapid salivation starts in our mouth. Also, it doesn't happen for all other food, which we eat regularly. So, Is there any particular use of "rapid salivation"? ...
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69 views

Does the body have a gate control for pain

I understand it is not the most accurate source but I recall a House episode where he claimed the body had a control mechanism for pain in which only the most painful thing was felt. Is that true? and ...
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183 views

What actually are thoughts? [closed]

The human brain consists of neurons that transmit impulses like wires that conduct electricity.I am confused about where are our thoughts stored and what really are thoughts? For example if I think ...
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226 views

How is consciousness linked to the brain?

Could the brain be working without consciousness? Does the brain interact with consciousness? Alternately, is it that consciousness can't really control the brain, and you only have the impression ...
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1k views

Why Do Nerve Signals Get Crossed?

First off, I don't know if this is a normal healthy thing to occur. There have been many times where I have an itch on say my arm and I scratch it, only to feel the scratching elsewhere on my body. I ...
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40 views

Does hypothalamus regulate posterior pituitary gland?

We have the hypothalamus-anterior pituitary-endocrine axis, but is there a similar chain of command for posterior pituitary gland such that oxycotin and vasopressin are regulated by some tropic ...
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231 views

Does playing music during sleep actually suppress rather than rouse the brain?

I've long been interested in the effect of music/sound on dreaming, and even built 2 apps that play music during REM period. Now I'm looking at this article about FMRI studies of a sleeping brain, and ...
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51 views

Effect of Ethanol on Brain Volume Measurements

I want to compare the brain sizes of two populations of fish. However, all the samples I have were fixed in 95% ethanol. As far as I know, 4% formalin is the normal fixative for soft tissues. Can I ...
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25 views

How were (many) dinosaurs' brains so small?

Brain size (or its proxy, encephalization quotient) usually varies allometrically with mass -- larger creatures need larger brains to control their larger bodies, apparently. Dinosaurs are popularly ...
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Does Alzheimer affect more than day-to-day memory?

I know that Alzheimer's damages a part of the brain called the hippocampus, which has a central role in day-to-day memory. But, could it affect also on things in other memory centers, things such as ...
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89 views

Brain regeneration - book recommendation

Searching for an up-to-date book on regenerative brain medicine with a focus on stem cell therapy. Also interesting in genetic engineering of neuronal stem cells for this purpose. Alternatively, a ...
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174 views

What are those visual and auditory reflex controlled by the midbrain? [closed]

The midbrain is a centre for certain visual and auditory reflexes. But what are those reflexes exactly? My study book says that these reflexes are, e.g., responsible for moving the eyes to view ...
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312 views

How do duplicate brain regions (ex: left/right amygdaloid body) operate together?

I frequently hear talk about parts of the brain like "Amygdala" or "Hypothalamus", so I looked them up in an app called "essential anatomy". What I see is that there's mirror symmetry, and most of ...
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350 views

What is the timing of information assimilation within a human brain? [closed]

A little background: I'm an avid dreamer and have great dream recall, sometimes up to 5-7 per night. In my experience, I can sometimes trace some elements of the dream to an event that occured ...
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78 views

How can neuronal signals faithfully be reproduced by scalp electrodes?

There is a skull barrier (and possibly other layers too) between the brain and the scalp. I have seen people trying to extract EEG signals from the scalp by connecting electrodes and interface it to ...
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997 views

Are Whales More Intelligent Than Humans?

Are Whales smarter than Humans? Their brain size leads me to think so.
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3answers
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Why is dopamine or a dopamine-receptor agonist not pumped into the brain of Parkinson patients?

I am aware that dopamine cannot cross the blood-brain barrier, but can't it be pumped inside the cerebrospinal fluid via some permanent tube implant? Wouldn't Parkinson patients chose that over ...
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1answer
91 views

Loss of appetite during fever

It is a well-known phenomenon that sickness like the common flu is often accompanied by reduced appetite. Why do sick people stop eating?
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1answer
464 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 ...
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360 views

Can dietary monosodium glutamate intake induce restlestness?

The question is all in the title. More context: I like phở soup. I have noticed that I get restless after eating the phở soup at some restaurants. The effects are similar to the ones resulting from ...
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524 views

When glucose production is low, the brain begins using ketoacids as energy… how does that work?

Can someone very generally describe how the brain consumes ketoacids/ketone bodies when blood glucose has been completely depleted?
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477 views

Is it possible to process electrical signals from the brain and interpret the results as exact thoughts?

If the brain uses extremely low voltage signals to communicate (from what I understand around 100 mV), what sort of breakthroughs would be necessary to intercept these signals and interpret them as ...
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246 views

EM Brainwaves VS Brain Wave (EEG) [closed]

The brain purportedly produces very weak EM waves. EEG is a method of measuring electrical brain activity, it has classifications for the types of brain wave it can detect: Theta, Alpha, Beta, Gamma ...
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181 views

What are the factors that control the speed of propagation of neuronal signals?

If we consider an analogy between a wire and a neuron there may be some resemblance between the factors controlling the data flow rate. For example the increased width of wire leads to decreased ...
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59 views

Why doesn't the rest of the body have something like the “blood-brain” barrier to protect itself from pathogens?

According to Wikipedia: "The blood–brain barrier acts very effectively to protect the brain from most pathogens". This is because the pathogens cannot pass through the tight junctions of the ...
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1answer
55 views

How can neurons divide without centrioles?

I have read in my studies that neurons lack centrioles. If that is so, then how is it possible that new neurons are added to our brain? Does this have anything to do with memory loss?
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How is information sent from limbs to the brain exactly?

Say you have a needle, and you poke a very specific area on your left thumb. A signal gets sent from that nerve up your spine and into your brain. How does the brain know exactly where this signal ...