Hot answers tagged brain
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Like these questions :) Many of these illusions come from Prof. Akiyoshi Kitaoka, a japanese Psychologist and expert for Gestalt Psychology. On his website you'll find some more fascinating illusions and questions to ask here ;)
The illusion above is named Cafe Wall illusion and the newest model to explain those illusions is the contrast-polarity model. ...
14
Regarding your question about losing synapses; yes, synapses are regularly lost in a process called Synaptic Pruning. From the Wikipedia article:
A decrease in synapses is seen after adolescence reflecting synaptic pruning, and approximately 50% of neurons during development do not survive until adulthood. Pruning is influenced by environmental factors ...
12
You would need to live a long, long, long, long time for this to become remotely problematic.
Your question seems to suppose that a memory is "stored" by a neuron, and since neurons have mass, then the more memories we have the more our brains will weigh. Actually, neurogenesis is pretty rare in the adult brain--most of the cortex is fixed, and new neurons ...
12
It is a phenomenon known as room amnesia, some research has shown that your brain may use physical barriers like the room and doorways as a way to compartmentalize thoughts.
One article summarizes it here:
The researchers say that when you pass through a doorway, your mind
compartmentalizes your actions into separate episodes. Having moved
into a new ...
10
Brain, indeed, cannot feel pain, as it lacks pain receptors (nociceptors). However, what you feel when you have a headache is not your brain hurting -- there are plenty of other areas in your head and neck that do have nociceptors which can perceive pain, and they literally cause the headaches.
In especially, many types of headaches are generally thought to ...
10
If you zoom in on the image, you can see that it is not just composed of black vertical lines, but also has pixels with different gray tones in the white areas. When you move your head sideways, you perceive the gray tones more.
If you were to remove the black lines, you could see the face clearly. Initially I thought that by blurring the gray shapes when ...
9
Its not clear that this is true.
Working with animals has been a little disconcerting over the past 50-60 years. In the distant past, I think most evolutionary anthropologists and their like bought into the idea that humans were completely uniquely intelligent and spiritual. But the more we try to define human sensibilities apart from other animals, the ...
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Just to get the ball rolling here. This particular aspect of brain evolution is very old. The cross wiring of the hemispheres of the brain seems to be as old as the right and left hemispheres itself. It predates lizards - i.e. hundreds of millions of years ago.
Digging back deeper, we can see that worms have bilateral brain structure, I would guess that ...
5
Just to echo what others have said here, the term lizard brain is a remnant of "recapitulation theory" which rigorously proposed that the embryo develops through more primitive animals. This is an intriguing idea when looking at embryos - early stage embryos of flies, birds, fish and primates really do resemble each other. So the idea was that our lower ...
5
The situation is definitely an extremely complex one, and you should probably forget about having an exact equation to define it.
When talking about the effects of a substance on the organism there are several factors to take into account. These are generally put together under the term pharmacodynamics.
Some of the factor to take into account are:
The ...
4
When I was in school it was discussed as an evolutionary survival advantage... If you are attacked from the right side, the left side of the brain is less likely to be damaged and can use the right sided limbs to fend off the attack as opposed to the right side being damaged and less responsive..
3
There have been many proposals over the years as to why human consciousness has emerged and how, or even what it is.
Most of us will not be surprised to know that there is no consensus about an answer here. Its hard to draw a trend from a single example.
Here is a little survey of the one's I've heard.
We are intelligent because we have opposable ...
3
You are probably referring to the suprachiasmatic nucleus.
Note that, although this is the central clock, there are also so-called "peripheral clocks", for instance in the liver, pituitary and other organs that can finely tune rhythms in the organism.
You may also want to have a look at the Wikipedia page for circadian clock and references therein.
3
The odds of that are really very slim. "Growing brains" in vitro is rather difficult, and it appears that no one has created the brain of a real organism, but they have created "brains" from cultured dissociated neurons.
Fusing brains is complicated by the fact that you need to make the appropriate synaptic connections between neurons, and what exactly ...
3
The average values of right hippocampus were recorded as follows weight 4.11572 gm, length 6.996 cm, width 1.998,volume 13.978 and surface area11.839 cubic centimetre while left hippocampus mean values were weight 3.96458gms,length 6.995, width 1.998,volume 13.976 and surface area 11.713cc. B. Narasinga Rao, K.R.S. Prasad Rao, R. Ramana Rao. 2012. ...
2
Know your databases! This is just the query fit for OMIM.
http://omim.org/entry/206500
Anencephaly is considered an extreme form of neural tube defect
(182940), which has been associated with variation in several genes.
The entity described here is believed to show autosomal recessive
inheritance.
The genes are those associated with neural tube ...
2
From what I've read and I know from my Biology classes, during the formation of the embryo a whole bunch of things may go wrong. In these cases, during the neurula stage, in which the brain is supposed to begin its development, something goes wrong while the neural tube is forming.
The causes? Some people argue that a lack of folic acid may lead to ...
2
You can definitely absorb alcohols by breathing them in. But doing do is far less efficient than drinking alcohol, so you don't have anything to worry about on that front.
To address your concern we have to answer two questions: how much alcohol is transfered per unit time and is there a local dosing effect due to proximity to the blood brain barrier.
It ...
2
I am not an expert in neurobiology, but this is what I have been able to find:
In general, the PNS (peripheral nervous system) does have remarkable neuroregeneration capabilities. However, the CNS (central nervous system), which includes the brain, has extremely limited neuroregeneration abilities. However, there are some interesting examples of CNS ...
2
Sleep is not homogenous - there are different phases of sleep - REM, NREM-1 to NREM-4. And these different stages may play different roles in 'rejuvenating' the body (as you put it).
When you first fall asleep, you go into NREM-1 phase, which is the lightest sleep, and progresses into NREM-4, and for the first half of your sleep cycle, this cycles so you go ...
2
http://www.turbosquid.com/3d-models/max-human-brain/580672
That one is only 30 which really isn't bad for a model. You will have trouble finding an anatomically correct model for free.
I am curious, is the male brain that much different from the female brain? And do you want just the brain or a whole head with the skeleton and other anatomical features? ...
1
After crossing the blood-brain barrier, toluene, along with other volatile anesthetic agents, had been previously thought to inhibit neuronal transmission by causing a change in membrane or membrane protein conformation. Recent research has shown that interactions with several key brain neurotransmitters, mainly γ-aminobutyric acidA (GABA), to a lessor ...
1
We already remove old ones and create new ones. I doubt you remember most of Geometry, for instance.
As for capacity, this article from Scientific American gives a good overview of what we can estimate with our current knowledge.
For comparison, if your brain worked like a digital video recorder in a television, 2.5 petabytes would be enough to hold ...
1
Speaking to Artem Kaznatcheev's comment, it is not true that the adult brain is post-mitotic.
Dr Bernard Rabin has shown is his scientific research, often in collaboration with and funded by NASA, that the adult brain is not post-mitotic, meaning that cell growth and division does occur. The primary focus of his work is to examine the relationship between ...
1
That the brain doesn't have pain receptors has somewhat drifted into the corpus of general knowledge, perpetuated by pamphlets, books and documentaries.
Your question caused me to look up wikipedia. Citing:
A headache or cephalalgia is pain anywhere in the region of the head
or neck. It can be a symptom of a number of different conditions of
the head ...
1
I thought this was an interesting subject and I had some time to do a little search around today. I can't find anything better than the review you point out. All I can do is add a few interesting notes since 2001. Nothing really turns over Rattenborg et al.
Sleep is itself a poorly understood process and most of the theories of the necessity of sleep can ...
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