[gwnn]

I always hear that the image on your retina is upside down but 'your brain turns it right side up.' But does this make any sense? If I had seen everything upside down since birth, would I ever notice? Similarly, if red and green were interchanged in my brain for some reason, would I ever notice? My brain would simply make the correspondence between the word 'red' and the sensation of (what other people regard as red, but what to me seems like) green. Help from other senses, e.g. touch or proprioception do not seem to help, since (I think) the correspondence between the sense of 'up' and the visual 'up' is arbitrary and is just made at some very young age.

I found this article http://en.wikipedia....tual_adaptation but it doesn't seem to address the basic issue (of whether the brain does anything at all in the first place, i.e. without the glasses).

[dwar0123]

If the brain didn't reverse the image, it would be very noticable. Merely waving my hand in front if my face would look odd, moving it up while seing it go down etc.

With respect to colors, probably impossible to notice directly, but I wonder if the way different colors interact with each other would still work out. Especially given that light mixes differently than paint.

[gwnn]

Seems like you are saying that there is an intrinsic 'up' and 'down' in sight that is automatically correlated to the 'up' and 'down' from the other senses (or equivalently, an intrinsic 'up' and 'down' to all senses). In the example of the moving hand, it would be the up and down of proprioception and the up and down of sight. Basically what I'm asking is, is there an invisible up arrow attached to sight? I know I am expressing myself less than perfectly..

[dwar0123]

If the image is reversed, the movement would be the reverse of what you felt like you were doing.

[gwnn]

 dwar0123, on 2012-December-30, 07:35, said:

If the image is reversed, the movement would be the reverse of what you felt like you were doing.

I understood the first time but I still don't understand why it is you are this sure about this. Why can't it be that someone sees everything upside down, simply relating (our) up to (his) down? The 'up' of proprioception to the 'down' of sight?

[1eyedjack]

There have been some well known experiments, in which individuals are required to use special spectacles/eyeglasses which flip/invert the image before it reaches the eye. So that, for a while at least, everything appears to the brain to be upside down to whatever it was previously accustomed. After a fairly short period of continous use (with associated confusion) the brain compensates and flips the image right side up again. Then, removal of the glasses flips the image upside down again, until after similar period of readjustment the brain compensates back again.

http://www.newscient.../eye-level.html


[EDIT] - sorry I see that the inital link considers this.
That being the case, I don't really understand the question.
All that the eye does is take an image and convert it into an electrical signal. Why should it matter what way up the image comes in? The signal just gets compiled like any computer program.

[gwnn]

My question was: if I were to see everything upside down since birth, would I notice (and how do I know that this isn't the case)? The experiments prove that the brain is capable of suitably rotating (and even mirroring, apparently?) of visual information, but that still doesn't help me, because I don't know what 'suitable' is.

[Fluffy]

I don't think you would notice and in fact I think that up is an abstract concept that you have associated with the lower side o images in your eye. The colors are also an abstract concept, but as far as I know the brain doesn't know what red and green mixed form except from experience.

Experience is the key, I read that (people living on the pole) have 27 or so scales of white, you first name it, then you learn to recognice and differentiate it from similar ones.

[barmar]

I've always had the same reaction as gwnn to this statement. The brain just needs to correlate retinal neurons with real-world orientation, and it learns early on from experience how they relate. Why should it care whether the physical location of the neuron is the same as that of the object being seen?

And as pointed out from that experiment, it can even unlearn the original orientation and learn a new one in a matter of days.

[lalldonn]

If my retinas didn't do this, would deuces seem high to me?

Gwnn is my favorite poster

[mike777]

Very interesting.

btw I read somewhere that for most of human life we did not have names or understand different colors.

think about that for human history we did not know most colors.

I should try and find some references that explains this better.


edit:

Benoit Mandelbrot discovered what is now called the M-Set in the early seventies and coined the term ... The Colors of Infinity

This may not be the most clear.....but at least a start.

[WellSpyder]

 lalldonn, on 2012-December-30, 15:17, said:

If my retinas didn't do this, would deuces seem high to me?

Yes, I think so - but you would expect the lowest card to win the trick, so deuces still wouldn't be as useful as aces.....

[Vampyr]

 WellSpyder, on 2013-January-14, 09:56, said:

Yes, I think so - but you would expect the lowest card to win the trick, so deuces still wouldn't be as useful as aces.....

This reminds me of a hand at the club Christmas party once -- after the auction, the rank of the cards changed. To alphabetical order. It was a real challenge figuring out who'd won a given trick.

[gwnn]

vsauce is reading BBF:
https://www.youtube....h?v=evQsOFQju08

[Zelandakh]

 mike777, on 2012-December-30, 20:53, said:

btw I read somewhere that for most of human life we did not have names or understand different colors.

Take a look at some old episodes of QI (or buy the book). One of the "quite interesting" tidbits is that the ancient Greeks described the colour of the sky was the same as the metal bronze (colour was more like we would call tone). It also explains that colours are added to almost every language in the same order, although I cannot remember what the order actually is. Some lesser developed languages are missing colours that most cultures would take for granted.

[barmar]

There's a TV show called "Switched at Birth", about a pair of families whose daughters were (you guessed it) switched in the hospital, and they discovered the switch when they were in high school. One of the girls became deaf as an infant, and much of the story takes place within the deaf community.

The thing that's relevant to this thread is that a few episodes ago, the deaf girl made an intentional pun when talking to a deaf friend. And last night, a bunch of deaf students were rapping, with lines that rhymed. I wondered how deaf people would know about auditory puns and rhymes. They can recognize the cases where the words (or final syllables) have the same spelling, but would they see that "tough" and "buff" rhyme? The lead dead girl has learned to speak, so I suppose she would, but many of the other deaf characters only seem to sign.

They were also putting on a performance of Romeo and Juliet in ASL. When the characters are signing, the show puts up subtitles with translations, and they used the archaic English style of Shakespeare. Does ASL actually have words for "thee" and "thou", which fell into disuse long before ASL was developed? I wonder if they were spelling all these old fashioned words out.

[blackshoe]

They might well have been spelling them out — ASL does have that capability.

[ArtK78]

 lalldonn, on 2012-December-30, 15:17, said:

If my retinas didn't do this, would deuces seem high to me?

This would explain why some of the people I play poker against do the things they do.

[barmar]

 blackshoe, on 2013-March-05, 13:56, said:

They might well have been spelling them out — ASL does have that capability.

I know that it does, although I assumed that it's only used sparingly, as a last resort. With all the archaic language in a Shakespeare play, it seems like it would drown in it, and obscure the poetry of the language. Does anyone know if ASL has a sign for "wherefore"? Or did she simply use the sign for "why" (thus avoiding the common misunderstanding that many modern people have about the most famous line in the play)?

I suppose it's not much different from translating Shakespeare into other languages. When his plays are performed in other languages, do the translators deliberately use old forms of the language, to give the same sense that it's from another period?