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Author Topic: Why Do We Blink With Both Eyes At The Same Time ?  (Read 13264 times)

Offline neilep

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Dearest Blinkologists....


As a sheepy I of course luff blinking. Blinking is my all time favourite eye-opening-and-closing thing that I do with my eyes.

Look, here's an example:







Eyes Open Moments Ago





Eyes Closed Also Moments Ago

Ewe may now consider the above eyes now blinked !..impressive eh ?


Now it has occurred to me that nature in her infinite wisdom has also given me the capability to close one eye and leave one open...thusly.



One Eye Open and One Eye Closed Thusly


Now then, we blink to keep our eyes moist yes ?..and wipe away grit, dust and stuff yes ?

Is it necessary  for our eyes to blink at the same time ?...why do they blink together ?..would it not be prudent to have each eye blink independently ?


whajafink ?



hugs & shmishes


mwah mwah mwah !


neil
Blinking Luffley
xxxxxxxxxxxxxx
« Last Edit: 11/03/2010 08:18:37 by neilep »


 

Offline Pwee

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Re: Why Do We Blink With Both Eyes At The Same Time ?
« Reply #1 on: 10/03/2010 18:51:01 »
neilep, this is one of the best questions I've red here in a while. This is really intriguing. It has to be taken into account that other blinking animals blink with both eyes too so it must be more efficient this way, but why?
 

Offline neilep

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Re: Why Do We Blink With Both Eyes At The Same Time ?
« Reply #2 on: 10/03/2010 21:31:09 »
I suspect that if we blinked one eye at a time, there'd be more babies born.  ;D

 ;D  ;D

 

Offline neilep

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Re: Why Do We Blink With Both Eyes At The Same Time ?
« Reply #3 on: 10/03/2010 21:32:29 »
neilep, this is one of the best questions I've red here in a while. This is really intriguing. It has to be taken into account that other blinking animals blink with both eyes too so it must be more efficient this way, but why?

Thanks Pwee  :)..lets hope a passing blinkologist passes by and comments !  ;)
 

Offline RD

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Re: Why Do We Blink With Both Eyes At The Same Time ?
« Reply #4 on: 10/03/2010 21:54:03 »
« Last Edit: 10/03/2010 22:07:41 by RD »
 

Offline neilep

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Re: Why Do We Blink With Both Eyes At The Same Time ?
« Reply #5 on: 11/03/2010 08:15:33 »
I'm gonna have to put a big post-it-note on my pc as a reminder !!
« Last Edit: 11/03/2010 08:19:03 by neilep »
 

Offline neilep

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Why Do We Blink With Both Eyes At The Same Time ?
« Reply #6 on: 11/03/2010 08:18:49 »
Done !
 

Offline Karen W.

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Why Do We Blink With Both Eyes At The Same Time ?
« Reply #7 on: 11/03/2010 08:22:19 »
Good boy Sheepy!
 

Offline RD

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Why Do We Blink With Both Eyes At The Same Time ?
« Reply #8 on: 11/03/2010 10:39:28 »
Done !

Seems successful from my end.


Re binking question.
With only one eye open you would be stereoblind, (no it doesn't meant you can't see your Hi-Fi  :) ).

If you blink eyes alternately objects in the scene appear to change their position (move) because of parallax. If you were a looking for the movement of prey or predator this apparent movement because of parallax would be a distraction: Looking for movement in an otherwise still scene is a lot easier then looking for movement in a moving one.
« Last Edit: 11/03/2010 10:43:23 by RD »
 

Offline Pwee

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Why Do We Blink With Both Eyes At The Same Time ?
« Reply #9 on: 13/03/2010 10:47:44 »

With only one eye open you would be stereoblind, (no it doesn't meant you can't see your Hi-Fi  :) ).

If you blink eyes alternately objects in the scene appear to change their position (move) because of parallax. If you were a looking for the movement of prey or predator this apparent movement because of parallax would be a distraction: Looking for movement in an otherwise still scene is a lot easier then looking for movement in a moving one.

I don't buy this. How is stereoblind worth than seeing absolutely nothing in the case of closing BOTH eyes?
Ok, you can argue, that it had to be 2 times more stereoblind periods than full blind periods if we assume that the eyes need the same amount of blinking, but I would think that it's still better to see something.

The picture gets more complex if you take into account that the brain compensates for the blinking, we rarely notice that we blinked, our visual field seems constant most of the times. We thought that this is due to the "iconic memory", that can store the whole visual field for some milliseconds. Now neuroscientists start to realize that there is a more sophisticated memory and computing capacity of the visual cortex that we didn't know of before. It can not only store the input, but it can perform computations like complex pattern recognition unconsciously that previously was thought to be only achievable by focusing attention. They think that this can be the background of Color constancy, and seemingly constant visual field during blinking and saccadic eye movements.

So if we have this kind of computing power in the background of simple (unconscious) perception and seeing that the brain can compensate for these blind periods during two-eyed blinking, we can safely assume that it would compensate for the one-eye closed stereoblindness too for that 300ms.
 

Offline Pwee

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Why Do We Blink With Both Eyes At The Same Time ?
« Reply #10 on: 13/03/2010 12:22:42 »
Another point against the stereoblindness hypothesis:



Every single animal blinks with both eyes at the same time, but some animals have almost no stereoscopic (binocular) vision. For example, Humans have a 120 binocular field, while rabbits have only 27, they are not relying on it that much. For a stereoscopic fields that small the downside of stereoblindness from one-eyed blinking would be negligible, but the bunny blinks with both eyes too.

Yes, the bunny blinks too, see video at 0:22
http://www.youtube.com/watch?v=7HiO9rzU_aw&feature=related
 

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Why Do We Blink With Both Eyes At The Same Time ?
« Reply #10 on: 13/03/2010 12:22:42 »

 

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