Does this imply Human brain photographic editing ability?

[Tnad]

1.LOOK AT THE YELLOW DOT FOR 10sec. 2.THEN LOOK AT THE BLANK AREA

 

 

I was amazed by this pic but most importantly by the final result. How by focusing for ten seconds on the yellow dot(which I call the center of gravity of the image), and then turning one's sight to the white/blank area, the image is reproduced in its actual/positive form. Does it have to do with the photographic ability of the human brain via the visual senses? does it imply that that the human brain has the ability of processing digital image data from negative(AS IN BLACK/WHITE) to positive (as in COLORED)? I can only make guesses but can't surely explain the implication of this wonderful realization.

Edited June 20, 2012 by Tnad

[iNow]

Does it have to do with the photographic ability of the human brain via the visual senses? does it imply that that the human brain has the ability of processing digital image data from negative(AS IN BLACK/WHITE) to positive (as in COLORED)?

No, this has nothing really to do with the brain. This happens at the level of the receptors in the retina of the eye (which get slightly fatigued from over-firing), and the effect is known as an afterimage.

 

http://faculty.washington.edu/chudler/after.html

Edited June 21, 2012 by iNow

[JustinW]

One thing that I have heard of that goes along with the title of the OP, if not the intent of the OP, is something called the color constant. http://search.yahoo.com/r/_ylt=A0oG7uGtfeNP2hkAw0ZXNyoA;_ylu=X3oDMTEyZW5xbmQ4BHNlYwNzcgRwb3MDMQRjb2xvA2FjMgR2dGlkA0RGUjVfNzc-/SIG=11t9ra1o3/EXP=1340337709/**http%3a//web.media.mit.edu/~wad/color/exp1/ This might explain it a little better than I can. It was rather interesting at any rate. When someone asks if we see things the same way as someone else, we can honestly say no. I was watching a show the other day that showed how different cultures were able to distinguish shades of color that other cultures couldn't because of their language. I'm sure there are plenty of other examples of the brain tricking us into see something that is actually different than the way we are precieving it.

[dimreepr]

One thing that I have heard of that goes along with the title of the OP, if not the intent of the OP, is something called the color constant. http://search.yahoo....wad/color/exp1/ This might explain it a little better than I can. It was rather interesting at any rate. When someone asks if we see things the same way as someone else, we can honestly say no. I was watching a show the other day that showed how different cultures were able to distinguish shades of color that other cultures couldn't because of their language. I'm sure there are plenty of other examples of the brain tricking us into see something that is actually different than the way we are precieving it.

 

 

I hope this doesn’t take this thread too far off topic, but as a biker I have been made very aware, from experience, that we are sometimes blind to what we’re not expecting.

 

 

http://www.theinvisiblegorilla.com/gorilla_experiment.html

 

http://www.simplypsychology.org/perception-theories.html

 

 

[Tnad]

No, this has nothing really to do with the brain. This happens at the level of the receptors in the retina of the eye (which get slightly fatigued from over-firing), and the effect is known as an afterimage.

 

http://faculty.washington.edu/chudler/after.html

 

Thanks for your reply. However, I failed to relate my example to the link you provided since your link shows a colored image that is reproduced hence the after-image. Although my pic shows a Non-colored pic that after staring at it for a long time it is reproduced and this time with Colors. Reason why I was thinking that there might be some kind of editing that is done since the final results produces something that's far different from the initial data.Though I agree with your information that this happens mainly at the eye/retina level, I'd like to know if there isn't any extension of the process that takes place at the brain level. Thanks again.

 

I hope this doesn’t take this thread too far off topic, but as a biker I have been made very aware, from experience, that we are sometimes blind to what we’re not expecting.

 

 

http://www.theinvisiblegorilla.com/gorilla_experiment.html

 

http://www.simplypsychology.org/perception-theories.html

 

Thanks for yr reply. I guess you are talking about cognitive bias as shown in yr link abt selective attention-invisible gorrilla(actually I tried the experiments but I saw the gorilla bcoz i expected to see one from the title however I tried it with a friend of mine who said which gorilla?' then I said you didn't see a gorilla and the friend exclaimed 'Oh yeah I saw a gorilla!' by which I concluded that my friend actually saw the gorilla but didn't percieve the gorilla. And I guess dimreepr was also refering to a similar kind of selective/biased perception which happens to all of us almost everytime. I even doubt if one can ever be absolutely irrational since we always have some sort of bias that we sometimes don't have control over. ENOUGH SAID, LET'S GET BACK TO THE INITIAL THREAD, I appreciate yr links that arised some interesting facts (although the yahoo link is dead-can't access it) but still HOW DID YOUR EXAMPLES ABOUT DISTORTED PERCEPTION RELATE TO MY INITIAL POST? DID YOU MEAN THAT ONE PERCEIVES THE SECOND IMAGE DUE TO ONE'S EXPECTATIONS? In any case, I'm still trying to understand the implications.

 

Thanks for all the replies. Keep them coming please!!!!!!

[iNow]

Thanks for your reply. However, I failed to relate my example to the link you provided since your link shows a colored image that is reproduced hence the after-image. Although my pic shows a Non-colored pic that after staring at it for a long time it is reproduced and this time with Colors. Reason why I was thinking that there might be some kind of editing that is done since the final results produces something that's far different from the initial data.Though I agree with your information that this happens mainly at the eye/retina level, I'd like to know if there isn't any extension of the process that takes place at the brain level. Thanks again.

No, only when interpreting the incoming stimuli, but that's not driving the effect you describe. Also, your image very much had color, and was not a "non-colored pic," so I'm unsure why you'd suggest the contrary.

[Suxamethonium]

I think it is from the fact that the when looking at the white background, you do not see the negative/colour inverted image you were originally staring at, but the inverse of the inverted image. Although the colour information is present in the original image, a function needs to be performed on that data to show it the way it is seen when staring at the white background. The retina definitely plays a role, however if the function isn't purely additive (i.e. staring at the negative and then the white has a subtractive (CMY) colour mixing effect) then surely part of the function must be made during the interpretation by the brain.

[Ringer]

I think it is from the fact that the when looking at the white background, you do not see the negative/colour inverted image you were originally staring at, but the inverse of the inverted image. Although the colour information is present in the original image, a function needs to be performed on that data to show it the way it is seen when staring at the white background. The retina definitely plays a role, however if the function isn't purely additive (i.e. staring at the negative and then the white has a subtractive (CMY) colour mixing effect) then surely part of the function must be made during the interpretation by the brain.

 

 

 

IIRC it has to do with your neurons not firing as strongly as they were before. Since you had an overabundance of the negative colors, by focusing on the center, those neurons wont fire as readily as the rest. Since color perception has to do with the colors that aren't being seen when you look at the white the colors opposite of the ones you were looking at should be seen. Either that or you see the after image and the brain does it's normal thing of saying, "Hey, it's a face. Let's put face colors on it."

[Suxamethonium]

"IIRC it has to do with your neurons not firing as strongly as they were before. Since you had an overabundance of the negative colors, by focusing on the center, those neurons wont fire as readily as the rest."

 

So that's kind of what I was saying- it's acting like a screen that "takes away" the negative from the white background, similar to a CMY mixing system.

 

"Since color perception has to do with the colors that aren't being seen" Are you sure? That completely invalidates additive (i.e. RGB) colour mixing. If we see colour based on what we don't see, then red and blue making magenta implies that you see magenta when you don't see any green (but you must then also see magenta when you see blue or red on its own because green is still not present). It would also mean that when seeing white (i.e. mixed red, blue and green) you should really see black as all receptors are being stimulated. Unless I have miss interpreted you.

[iNow]

Suxameth - You should spend some time at sites like this to satisfy your natural curiosity on these issues: http://faculty.washington.edu/chudler/retina.html

 

http://www.hhmi.org/senses/

 

(specific to color perception: http://www.hhmi.org/senses/b110.html )

[Ringer]

"Since color perception has to do with the colors that aren't being seen" Are you sure? That completely invalidates additive (i.e. RGB) colour mixing. If we see colour based on what we don't see, then red and blue making magenta implies that you see magenta when you don't see any green (but you must then also see magenta when you see blue or red on its own because green is still not present). It would also mean that when seeing white (i.e. mixed red, blue and green) you should really see black as all receptors are being stimulated. Unless I have miss interpreted you.

 

I am terrible at explaining color theory so I'll just give you a link on what I meant:

http://en.wikipedia.org/wiki/Opponent_process

[iNow]

To be clear, we don't "see color." We have three different visual receptors in the retina known as "cones." These cones tend to react to fairly restricted wavelengths of light, and that reaction is a chemoelectrical response wherein sodium/potassium channels rapidly open and close changing the polarity of the nerve cell, and that response cascades through the nervous system via action potentials. Some of these receptors fire more strongly when receiving more reddish wavelengths, others fire more strongly when receiving greenish wavelengths, and the third kind peak when receiving blueish wavelengths.

 

The brain then takes the signals from each of these cone cells, and based on the signal strength, the source location, the timing, etc... will do something analogous to an unconscious Fourier transform... and ultimately what we call that is a result of what we've been taught... We call it "magenta" or "brown," for example.

 

 

http://en.wikipedia.org/wiki/Cone_cell

 

Humans normally have three kinds of cones. The first responds the most to light of long wavelengths, peaking at a reddish colour; this type is sometimes designated L for long. The second type responds the most to light of medium-wavelength, peaking at a green colour, and is abbreviated M for medium. The third type responds the most to short-wavelength light, of a bluish colour, and is designated S for short. The three types have peak wavelengths near 564–580 nm, 534–545 nm, and 420–440 nm, respectively.[8][9] The difference in the signals received from the three cone types allows the brain to perceive all possible colours, through the opponent process of colour vision. (Rod cells have a peak sensitivity at 498 nm, roughly halfway between the peak sensitivities of the S and M cones.)

 

All of the receptors contain the pigment photopsin, with variations in its conformation causing differences in the optimum wavelengths absorbed.

 

The colour yellow, for example, is perceived when the L cones are stimulated slightly more than the M cones, and the colour red is perceived when the L cones are stimulated significantly more than the M cones. Similarly, blue and violet hues are perceived when the S receptor is stimulated more than the other two.

 

The S cones are most sensitive to light at wavelengths around 420 nm. However, the lens and cornea of the human eye are increasingly absorptive to shorter wavelengths, and this sets the short wavelength limit of human-visible light to approximately 380 nm, which is therefore called 'ultraviolet' light. People with aphakia, a condition where the eye lacks a lens, sometimes report the ability to see into the ultraviolet range.[10] At moderate to bright light levels where the cones function, the eye is more sensitive to yellowish-green light than other colors because this stimulates the two most common (M and L) of the three kinds of cones almost equally. At lower light levels, where only the rod cells function, the sensitivity is greatest at a blueish-green wavelength.

 

Cones also tend to possess a significantly elevated visual acuity because each cone cell has a lone connection to the optic nerve, therefore, the cones have an easier time telling that two stimuli are isolated.

 

Note: There is another type of receptor in the retina known as "rods," but those are more for movement and on/off sensation of light... Color is not involved with those, just light and darkness, and they tend to more toward the periphery of our vision.

[Ringer]

Really rods are used for the majority of our vision, the brain just does its whole lying to you thing. A fun trick to show how color blind we are until something centers in our vision is to have a friend have different color cards, or anything with different solid color, and look straight ahead. Have the friend slowly bring the cards into your field of vision from behind you and see how long the different is between when you see the card and when you can tell what color it is.

 

[edit]

 

More stuff for mind trickery look at the books mind hacks and slights of mind.

http://mindhacks.com/

http://www.sleightsofmind.com/

 

[/edit]

Edited June 28, 2012 by Ringer

[iNow]

Really rods are used for the majority of our vision, the brain just does its whole lying to you thing.

Indeed.

 

http://en.wikipedia.org/wiki/Photoreceptor_cell

 

The human retina contains about 120 million rod cells and 5 million cone cells. The number and ratio of rods to cones varies among species, dependent on whether an animal is primarily diurnal or nocturnal.