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Yes. You are referring to a classic experiment in Perceptual Adaptation from 1896: George M. Stratton, Some Preliminary Experiments On Vision Without Inversion of the Retinal Image (Read at the Third International Congress for Psychology, Munich, August, 1896.) Here's a video from a BBC documentary reproducing the experiment. You can also check this book ...


53

From HubbleSite - Behind The Pictures: The Meaning of Color The colors in Hubble images, which are assigned for various reasons, aren't always what we'd see if we were able to visit the imaged objects in a spacecraft. We often use color as a tool, whether it is to enhance an object's detail or to visualize what ordinarily could never be seen ...


38

TLDR : Yes. A person wearing glasses that inverted the vision would in a few days adapt and perceive the vision as normal. see Perceptual Adaptation George M. Stratton, a psychologist, was intrigued by the idea of perceptual adaptation. Because the retina receives images upside down, he was intrigued to see what happens when the brain receives an ...


34

TL;DR: The claim is actually false. Cats and Dogs (as well as many other animals) just see the world differently from humans. We would call them colourblind, but not greyscale colorblind. I run into this claim A LOT, so I feel that it is indeed a great skeptical claim. At the very least a teaching moment to introduce what skepticism means since this is ...


29

Snopes lists it as unproven. http://m.snopes.com/camera-flash-blind-baby/ The Daily Mail pointed to the unreliable People’s Daily Online as the source of this information, who in turn sourced their story from Guangming Daily, who sourced their reporting from QQ.com, who cited DAHE.com, who got their information from Henan TV. At no point in this ...


22

I don't think this is correct. Your eye muscles might get 'tired' but there's no reason for damage to the eye to occur in terms of vision. Our eyes have evolved to compensate for motion very well. There is a similar myth that reading in low light damages the eye. You're more likely to have a problem with car sickness. This is thought to be caused by a ...


16

The "damage" done by screens is in the form of eye strain. Your eyeball focuses by using muscles in the eye to change the shape of the lens within the eye, to properly focus incoming light onto the correct portion of the retina. It is the second part of your eye, after the cornea, that helps to focus light and images on your retina. Because the lens is ...


15

In Australia, there is a mandatory standard for the labelling of sunglasses to help the consumer. In 2003, the Australian Competition and Consumer Commission (ACCC), a consumer watchdog issued a Regulation Impact Statement about the standard. Here is an historical copy. In the document, they discuss the risks of poor-quality sunglasses. Some are ...


12

Yes, the eye can distinguish frame rates above 60 Hz. So can the brain. We are just not normally aware of it. Conscious perception of flicker is measured in laboratories using the critical flicker frequency (CFF) threshold, which is the lowest frequency of flickering light (Hz) that produces the appearance of steady light in an individual. It's a ...


11

Yes, it can, just as much as reading or any other activity where you're looking at something close to your eyes. "Optometric Clinical Practice Guidline: Care Of The Patient With Myopia": Doing a substantial amount of near work on a regular basis can increase the risk for myopia. Myopia is associated with greater time spent reading and doing near ...


11

The claim at Quora is close to the mark, although not exactly for the reason claimed. All lenses (including our eyes) suffer from chromatic aberration, a kind of distortion that occurs because different colors have different refractive indexes. In photographs, this distortion results in fringes of color in high-contrast areas. In eyesight, it can increase ...


11

What you described sounds like the Absolute Threshold in neuroscience. It is commonly defined as "The lowest amount of stimulus that a person can detect 50 percent of the time." According to an experimental research conducted by Hecht, Shlaer, and Pirenne (1942), the smallest number of photons that could elicit a visual experience is 90 photons, while ...


11

Yes, it is recognised as a potential problem: LED lighting flicker and potential health concerns: IEEE standard PAR1789 update. The IEEE Standards Working Group, IEEE PAR1789 “Recommending practices for modulating current in High Brightness LEDs for mitigating health risks to viewers” has been formed to advise the lighting industry, ANSI/NEMA, IEC, ...


10

To the human eye, nebulae always appear overwhelmingly B&W. Human dark-adapted eyes are much more sensitive to B&W (wikipedia) and their color sensitivity shifts. There are only a few nebulae that are reliably visible to the naked eye and your pupil just can't pick up enough photons to detect color. This discussion of amateur astrophotography breaks ...


9

Refresh rate: First of all, in case of modern flat screens, be it LCD or OLED, refresh rate is misnomer. It's actually frame rate — rate at which the TV is able to change image from one frame to another. Pixels on these panels are constantly on, thus there is no flicker on LCD or OLED. On the other hand, CRTs had refresh rates, since pixels would glow ...


9

While the immediate effect of increasing focus at the expense of "lightness" is well established, there seem to be no studies supporting long-term vision improvement. In fact, companies selling this product in the United States are not allowed to claim any long-term effect due to the lack of formal clinical studies. According to Casewatch: In four ...


8

This should really be a comment, as I have only partial information and am neither able to conclusively strengthen or refute the claim, however I can throw some information into the debate. I'll start with the part of the claim that "specifies" what happens: eventually needs glasses Besides the (trivial) fact that almost everyone eventually needs ...


7

No, watching too much television does not directly cause myopia. Walter Wood has debunked the theory that too much near work causes myopia. In his book The Ultimate Unification of Diet Health and Disease he makes the following points/observations: In a study published in January 2011 80 7-11-year olds were randomly assigned into intervention or ...


7

They may be beneficial from the American Optometric Association: Eyeglasses or contact lenses prescribed for general use may not be adequate for computer work. Lenses prescribed to meet the unique visual demands of computer viewing may be needed. Special lens designs, lens powers or lens tints or coatings may help to maximize visual abilities and comfort. ...


7

Assuming you are talking about what is commonly know as "lazy eye" or amblyopia from a medical standpoint, then yes patching the dominate eye is a common treatment that is used (see also, 1, 2, 3, 4). However, other treatments such as eye drops may be used to force the weaker eye to get stronger by blurring the vision in the dominate eye. When should ...


6

There are more problems which can occur from "staring" on screen. Eye discomfort Headaches Itchy eyes Dry or watering eyes Burning sensations Changes in color perception Blurred vision Difficulty focussing (1, 2, 3) Ways to minimise damage to your eyes caused by computer screens There are several ways you can minimise the potential damage to your eyes ...


6

A new perspective on spontaneous blinks Ophthalmology 2013 May; 120(5):1086-91 Blink rate was significantly higher in women than in men (P = 0.007, unpaired t test; female, 22.0 ± 16.8 blinks/minute; male, 8.6 ± 7.2 blinks/minute). See also Analysis of blink rate patterns in normal subjects Movement Disorders 1997 Nov;12(6):1028-34. Women had a ...


5

The title of the question asks if most blindness solved by cadaver donation? The World Health Organization states that: According to the latest assessment, cataract is responsible for 51% of world blindness [1] So, cataracts are responsible for the majority of blindness. Cataracts are readily treated by replacement of the lens of the eye with an ...


5

Personal computers are possibly one of the most empowering tool humanity has ever created. They're tools of communication, creativity, and they can be shaped by the user. But, of course they "computers" come with various negative effects. One negative effect is affecting your eyesight. Computer users (including me) have reported many eyesight problems like ...


5

This page, which includes relevant calculations, suggests a limit closer to 10km. The calculations compare seeing a candle to seeing a 6th magnitude star. There's additional discussion assuming an ability to see 7th and 8th magnitude stars, but 6th is generally considered the naked eye limit. Even 10km strikes me as ambitious, since it does not take into ...


5

Referring to Martin Gardner in the book 'Fads and Fallacies in the Name of Science' Chapter 19 'Throw Away Your Glasses', there had been no changes in the cornea opacity of Aldous Huxley to indicate better or improvement in vision due to the alternative Bate's method therapy. The following quotation is from Bennett Cerf's column in The Saturday Review, ...


5

Summary: complete colour blindness is very rare (less than 0.01%). What's common is deficiency in red-green colour vision in men, which is around 8% (sex-linked because it's from an X-chromosome fault). This is based on a huge amount of evidence from accurate, widespread diagnostic testing. You're unlikely to notice it in another person through normal ...


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