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18

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. ...


17

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 ...


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 ...


13

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 ...


12

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 ...


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 ...


11

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 ...


11

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 ...


10

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..


10

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 ...


8

To quote the University of Sidney site: People often think that other people are staring at them even when they aren't research led by the University of Sydney has found. When in doubt, the human brain is more likely to tell its owner that they're under the gaze of another person, researchers from the University of Sydney and The Vision Centre ...


8

It's less a problem of speed and more of raw photon count. Assuming a brightly lit day, the bullet will move so fast that it doesn't reflect enough photons to register against the background. High speed images of bullets usually involve a very bright flash (and other controlled settings) for the camera to pick it up. (Also, a very short flash helps the ...


7

You are correct in that the neurons themselves do not sense pain. However, the brain contains layers of coverings, blood vessels, the scalp and some muscles. All of these other structures have pain receptors. The coverings of the brain are called meninges and consist of the dura, arachnoid and pia. The dura in particular has a lot of pain receptors and may ...


7

Briefly the "Stoned Ape theory" posits that psychoactive Psilocybin mushrooms in the diet of pre-Homo sapiens primates catalyzed the change Homo sapiens. It suggests that the mushrooms conveyed selective benefits to consumers of the mushrooms, dissolving the 'egos' of our ancestors and allowing them to form communities. It may also be sexual stimulant, ...


7

The temporal lobe is in the temporal region of the head, near the temples of the skull, hence the name. It's name does not relate to it's biological function, it is mainly involved in processing language, visual memories, and emotions. The medulla oblongata is one region of the brain that deals with a lot of the "tempo" type functions (tempo as in keeping ...


6

The current working theory (note this is still an open question, but there are many leads being followed): Sensory systems receive a combination of signals from an event, which are initially bound to the hippocampus (this is called episodic memory). Then, typically during sleep, the memories are consolidated. A simplified view is that consolidation ...


6

The idea that memories could be stored as RNA or proteins is an old one. It got a lot of attention decades ago when James McConnell did a number of experiments where he conditioned planarian flatworms to respond to certain stimuli, ground them up, fed them to worms that hadn't gone through the conditioning. He claimed to have observed that the worms fed ...


6

Refute? No. Shigeta summarized the work pretty well, and though I have my own opinions on McKenna's theory the fact is that Darwin and McKenna are not opposed. The "Stoned Ape theory" is a specific idea for how human intelligence might have appeared from earlier hominids. Darwin (and Wallace) proposed a broad theory that has borne out for the process of ...


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

As the father of two sons with diagnoses of ASD, I think that it is best to think in terms of an extended spectrum which encompasses 'normal' people. We are all somewhere on this spectrum, but there is a threshold zone around where we cross from "normal" to "diagnosable as ASD". Now, if the distribution of spectral position for males is displaced towards the ...


4

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 ...


4

Not so empty, actually. The human brain has a mass of ~1.5kg, and volume ~1200cc (a little bigger for men, a little smaller for women). So is heavier than water by a good margin. While it has Cerebrospinal fluid, that only occupies the subarachnoid space (the space below the skull and above the cortex, contained between two layers: pia matter and arachnoid ...


4

It seems there's way too many variables here. Crushing can occur in a number of ways, leading to different primary damage in different regions first and different people have a different level of system failure thresholds. Technically, there are no pain sensors on the brain, so you wouldn't feel any pain in the classical sense. However, it's hard to ...


4

V1-V5 are different (sub) regions of the visual cortex itself. via http://www.tecsyn.com The layers L1-L5 (some regions have a layer 6) refer to the different cellular strata in the depth dimension of the cortical mass. This stratification occurs to some extent or another in various areas. Different sections of the cortex, e.g., the primary motor ...


4

There is no widely-accepted neurological structure that mediates 'consciousness.' Even if some structures have been shown to be necessary for consciousness, they have not been shown to be sufficient. This is true with anesthetic mechanisms as well -- their ability to paralyze and block pain signals is fairly well-understood, but the mechanism of ...


4

Yes, they do. A blog post on the National Geographic website describes the results of a study about how blind people dream.(1) The participants who were born blind did not report any visual impressions. Among those who previously had sight, the number of visual impressions reported decreased with the time since loss of sight. Just as there are many ways ...


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

This is a common phenomena which most of us come across. Seeing flashes of light, stars and other shapes in the eyes occur when the body goes through stressful activities. For example while you are climbing the blood flow will be more to other prominent parts like hands and lower waist so brain and eyes will get less supply of blood as well as nutrients. ...


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. ...


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.



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