Why might reading make people myopic?

http://www.eye-tuebingen.de/the-institute/news-events/news/news-article/60-why-might-reading-make-myopic/

by amai • 8 years ago

116 74 8 years ago

alexgmcm4• 8 years ago

"One would therefore expect that dark text on bright background would stimulate myopia development and bright text on dark background would inhibit myopia."

Another reason to use dark themes.

istjohn• 8 years ago

I suspect this effect is far weaker--if even present--in adults.

alexgmcm4• 8 years ago

Yeah - my eyesight is already really bad, but hopefully there will be something like a Kindle Paperwhite with dark theme so my future children won't have to suffer the same.

anotheryou2• 8 years ago

It seems very much fluctuating for me. I had days where it was really bad and days where it's non-existent.

Santosh83• 8 years ago

But how to invert the colour of web pages? Dark themes darken the UI but the webpage is almost always still dark text on light background.

anvandare• 8 years ago

If you're on linux: `xcalib -i -a` turns everything negative.

kroltan• 8 years ago

Just add the

    filter: invert(100%);

style's on a page's HTML. There are userscripts that do that automatically for you.

kbutler• 8 years ago

There are lots of addons available - here is a highly rated one: https://darkreader.org/

lordnacho• 8 years ago

Stylus Chrome extension has alternative styles for loads of websites. Eg I make GitLab dark with light text using a downloaded style sheet that someone made, and my HN as well.

jraph• 8 years ago

On Firefox you can use Dark Background and Light Text. Also works on Firefox Mobile, good results with a led screen.

walterbell2• 8 years ago

Triple-click home button on iOS, via accessibility settings.

Tharkun• 8 years ago

Ugh. Dark themes. Can't get used to them. Fine for general terminal use, but impossible for me for larger amounts of text. Can't really articulate why, but it's uncomfortable for me.

crazygringo3• 8 years ago

There's lots of research showing that people read black-on-white body text significantly more accurately/faster (around 25-30%), so that's normal.

saalweachter• 8 years ago

I actually keep my Kindle white-on-black.

nbeleski• 8 years ago

I remember recently reading about the myopia increase in China and it was largely attributed to children staying much more inside, out of the sunlight, causing the eye to under-develop iirc.

I wonder how much these are correlated.

delecti• 8 years ago

Myopia is actually caused by your eye being "too long", and means the lens focuses light in the middle of your eye, rather than on the retina. It seems that sunlight ceases the development of your eye, rather than encouraging it.

Perhaps we evolved to "make use" of UV light to halt our eyes growth.

madeuptempacct2• 8 years ago

https://www.npr.org/sections/goatsandsoda/2015/02/05/3837653...

There was a study that followed Chinese kids who stayed in China vs Chinese kids who moved to Australia. There was a marked difference.

Not sure if its about sunlight or near/far focus though.

Apocryphon• 8 years ago

They can test this if they tried getting students to try studying outside under natural lighting for a while. Though in China that may be impractical depending on the city.

jacobolus• 8 years ago

Not sure if its about sunlight or near/far focus though.

I have seen some suggestion that it is a combination of both. Either is plausible though.

sandworm101• 8 years ago

I read that it isn't a sunlight issue, but an overall brightness issue. If that is true, reading on a bright screen might be better than reading a book.

011000113• 8 years ago

I thought it was caused by a shortage of dopamine caused by a reduction in sun exposure.

https://www.ncbi.nlm.nih.gov/pubmed/23434455

arendtio• 8 years ago

Thank god, terminals have dark backgrounds by default :D

4ad• 8 years ago

What default is that?

alexgmcm4• 8 years ago

Also I wonder if this means TV and Video Games etc. aren't as bad for eyesight as they should have the same visual statistics as natural scenes (as they display natural scenes more or less) despite TV being demonised as bad for eyesight for generations.

Whereas when you think about it staring at dark symbols on a bright background is really unnatural and therefore it is reasonable that it can affect visual development.

theriddlr• 8 years ago

Could be CRT vs. LCDs. Family all have bad eyesight but my younger sister who spends every waking hour gaming doesn't need glasses. I spent less time on the computer when I was her age but I had a CRT monitor.

madeuptempacct2• 8 years ago

I am a 99% sure that "some people are just immune." I have friends my age who played games way more with perfect eyes. I also have a friend who drank soda at work all day and never had a single cavity.

doombolt• 8 years ago

We should take their genes responsible for that, put it in our future embryos.

Essentially turning "genetic lottery" into "genetic basic income".

gwbas1c• 8 years ago

When I was a teenager I preferred white text on a black background. (Think of the DOS terminal.)

In my very early 20s, I suddenly found white text on a black background extremely irritating. Suddenly, my vision was filled with persisting horizontal lines. (Like what you get when you look quickly at a light bulb.)

Maybe it's because DOS was really grey on black, but on the web, people typically do bright white on black?

VLM• 8 years ago

Web era began around the rise of LCD displays. CRTs are too non-linear for most people to tolerate black on white, so its a status symbol from around the turn of the century to do white on black.

Not helping matters is the rise of glossy distraction screens, again before the turn of the century the status symbol was ultra low glare matte screens to avoid eyestrain and with the conversion to everything must be shiny its hard to look at a black background reflecting tons of distracting moving shadows so everything must have a white light blackground to cut thru the bright distracting reflections.

crazygringo3• 8 years ago

CRTs are too non-linear for most people to tolerate black on white

What does non-linear mean? And what do you mean tolerate?

Before LCD screens all Macs were black-on-white and people loved it. The first Macs were monochrome. I don't recall anyone ever having a problem with it.

Also, I don't remember any matte CRTs -- they're all glossy because their surface is glass.

Really confused as to what you're talking about.

boomlinde• 8 years ago

Web era began around the rise of LCD displays. CRTs are too non-linear for most people to tolerate black on white, so its a status symbol from around the turn of the century to do white on black.

How does this account for things like Atari TOS, MacOS, OS/2 or any early version of Windows that all mainly use black on white for text? The "web era" depending on how you define it could of course have coincided with the LCD era (though in my experience happened more than half a decade earlier, which is generations in computer technology time) but the web didn't somehow invent black text on white backgrounds.

matwood• 8 years ago

I've always preferred a sepia type color scheme. The HN default colors are pretty close to perfect for me. Solarized Dark color scheme is about as dark as I like to get. Going full black background on white text has always been hard for me to read.

0x8BADF00D2• 8 years ago

Solarized Dark is great. I use it and Inconsolata when coding. Highly recommend it. Zenburn is decent too, if you want something even darker.

0x8BADF00D2• 8 years ago

I typically use Solarized Dark, with a bit of customization. That’s easy on my eyes throughout the day.

freeflight• 8 years ago

I still prefer dark background with white text to this day, even when the web came around I tried to keep all my software/OS with dark background/white text. To this day I'll try to use "night mode" if available.

It's so much less strain on the eyes, especially during the night or after waking up. Going from darkness to a blazing white screen literally hurts in the eyes.

Retr0spectrum• 8 years ago

Yes, I get that too! (The persisting lines)

When I'm forced to use black-on-white (i.e. when browsing most of the web), I find that reduced brightness and increased monitor colour temperature helps a lot.

011000113• 8 years ago

When I was a teenager I took a big dose of what I thought was blotter acid. I ended up with HPPD and ever since I have trouble looking at dark text on a white background. Sucks... I used to be a speed reader and now I'm maybe only a little faster than average.

My normal color scheme is a slightly modified 'desert' theme that comes with vim.

tobr• 8 years ago

Am I understanding this right? The choroid layer behind the retina gets slightly thinner when we look at dark details on a bright background, and slightly thicker when we look at bright details on a dark background, and somehow this causes an opposite effect in the overall eye growth over time. So spending a lot of time looking at dark letters on a bright background would cause the eye to become too long and unable to focus on objects far away.

Is there an explanation for why the choroid changes its thickness, and why this change would create an opposite effect in eye growth over a longer period?

philipswood3• 8 years ago

So, they eye works pretty much like a camera - but it's not a camera: it's a complex dynamic self-assembling, self-tuning adaptive structure.

The fact that it's geometry is roughly static around a focal length that has sharp focus on the retina is a wonder of homeostasis with at least three known tuning loops: 1) the lens Moving on swiftly... 2) a slower feedback loop adjusting the choriod (hence focal length) in the order of hours. 3) an even slower loop adjusting the eye geometry over longer periods of time.

philipswood3• 8 years ago

The story so far: We hack our visual sense to be a data channel for symbolic information. This incidentally messes with the above homeostatic loops causing myopia. We then hack the eye's optics to correct the immediately problem without fixing the cause and oppose the corrective process by adding glasses or contacts.

We end up at a myopic static point where the balance of forces match.

Big lens wins.

DrNuke4• 8 years ago

There are a few gym protocols used to train / flex / exert the eyes’ muscles and revert myopia gradually. An expert tutor acting under your doc’s supervision is needed, though.

elektor• 8 years ago

What you're describing is the Bates Model, which has not been objectively shown to improve eyesight.

DrNuke4• 8 years ago

Nah, there are more recent studies based upon first principles and less stretching protocols than Bates. Still not accepted best practice, though, so individual mileage may vary, my myopic eyesight improved enough to give them a pass.

tralarpa3• 8 years ago

...muscles...myopia...

This combination of words doesn't make any sense.

keldaris4• 8 years ago

Not quite true. The ciliary muscles and suspensory ligaments in your eye are largely responsible for ensuring the accommodation-convergence reflex (the process by which your eye focuses on objects at different distances) works properly. It's not a priori non-sensical to assume that actions (exercises, drugs, etc.) that affect the ciliary muscles could change the accommodative properties of the eye sufficiently to decrease the effects of myopia - in fact, that's a part of what happens when you get atropine drops during an eye exam.

Note that this is not an endorsement of Bates' or any other method supposed to implement this in practice. I'm just noting that putting "muscles" and "myopia" in the same sentence isn't non-sensical.

k__2• 8 years ago

I'd say "well that explains everything" after I spent most of my time before a monitor since I was ten.

But I'm not myopic, but astigmatic.

walterbell2• 8 years ago

How is your neck posture? Reading sideways in bed can also affect visual cortex.

k__2• 8 years ago

Never did that. Felt rather tyring quick

fhood• 8 years ago

However this is also necessary since we have about 125 Million pixel in the retina but only about 1 Million “cables” in the optic nerve.

Just switch to a busable protocol. I don't see what the issue is here.

011000113• 8 years ago

So does this mean that my preferred color scheme of light text on a dark background might be accelerating my presbyopia? I'm at the perfect age for it to start(43), but it sure seems to be progressing fast.

matt-snider• 8 years ago

As a German speaker, this title seems very Denglish-ey to me. Is this phrasing valid in English? It seems like the object of 'to make' is necessary and missing, whereas in German it is perfectly normal and correct to phrase things this way (e.g. Tofu macht satt, or Schnaps macht betrunken, whereas in English you'd say: tofu makes you full/is filling, or shnaps makes/gets you drunk).

Not trying to nitpick, just curious if this is actually correct grammar or not.

jackpirate• 8 years ago

As a native English speaker, you're correct.

stephenhuey• 8 years ago

I’m also a native speaker, and I find this construction recognizable from some literature. Just searched for examples of whether a grammar teacher would allow transitive verbs without direct objects, and I found one of the answers here suggesting it’s ok in English because the object can be inferred from context:

https://ell.stackexchange.com/questions/43482/a-transitive-v...

Why might reading make people myopic?

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