Whether we know it or not, we can 'see' through one eye at a time

October 17, 2011

Although portions of the visible world come in through one eye only, the brain instantaneously takes all that information and creates a coherent image. As far as we know, we 'see' with both eyes at once. Now a new study suggests that the brain may know which eye is receiving information -- and can turn around and tell that eye to work even harder.

“We have demonstrated for the first time that you can pay attention through one , even when you have no idea where the image is coming from,” says Peng Zhang, who conducted the study with University of Minnesota colleagues Yi Jiang and Sheng He. And the harder that eye is working -- the heavier the “informational load” -- the more effectively still that eye can attend to its object. The findings will appear in an upcoming issue of Psychological Science, a journal published by the Association for Psychological Science.

The researchers conducted two experiments, each with six observers ages 20 to 29, who viewed images through a mechanism that can separate stimuli by eye. In the first experiment, in one eye a target—which looked like a shiny compact disc -- gradually emerged in a sweeping fashion. In the other eye a “noise patch” of high-contrast flashing colored squares was displayed. Each image was in the same spot relative to its respective eye, so the two appeared in the same place in the field of vision; the target seemed to displace the patch as it came into view. A small round “cue,” either in the target eye or the noise eye, also gradually turned from red to gray or back and got fat or thin. Participants had to press a button when it turned, say, red or fat and gray. At the same time, they had to press as soon as they saw any part of the target appear.

The viewers took less time to notice the emerging target when it was in the same eye as the cue.

In the second experiment, the task was harder. Two cues were displayed at once and participants had to attend to both or to two “features” at once—indicating for instance when both were red or both red and thick. Like tougher training improving an athlete’s performance, the additional “load” forced that eye to work harder—and, the researchers found, enhanced that eye’s abilities further. Again, the target appeared even faster when the cues were in the target eye and even slower when they were in the noise eye.

The findings, says Zhang, suggest some intriguing things about the visual system. “Maybe there are binocular neurons in the brain” -- neurons that take in and collate information from both eyes -- “that also know which eye that information is coming from and can feed back to that eye,” telling it to pay closer attention. In other words, the mechanisms of visual perception, and the communications between eye and , may be even more flexible and powerful than scientists thought.

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not rated yet Oct 17, 2011
A friend was born with only one functioning eye. He has no trouble forming 'coherent' images. He has held a CDL and is a semi-professional photographer. He feels having monocular vision improves his photography.
not rated yet Oct 17, 2011
I am wall-eyed and have peripheal vision like a monster. People I worked with thought I had eyes in the back of my head, I just thought most people have tunnel vision.


Makes it very easy to discern small changes in my visual field that would normally skate right by most people, also chunking when reading is a breeze.
not rated yet Oct 18, 2011
Don't know about you guys but I also have what's known to most laypeople as " visual snow " , quite strongly.

Visual Perception of Stochastic Resonance


The conclusion:

" These experiments have demonstrated the utility of SR
as quantitative measure of the efficiency with which the
visual system processes noisy information. The repeatability
and stability of the measure for individual subjects
suggests that it may become useful as a diagnostic tool
in tracking or detecting visual impairments in humans or
in selecting individuals with ---exceptional ability (small K)
to perceive and interpret fine detail within noise contaminated images.-- "

So being wall-eyed and having visual static might actually be beneficial ?

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