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Study: Light-Emitting Screens Before Bedtime Disrupt Sleep 179

Posted by Soulskill from the why-you're-tired-all-the-time dept.
jfruh writes: Tablets and e-readers are more convenient in many ways than paper books, but many people have complained that the physical experience of using them isn't as good. And now we have some specific quantification of this fact: a study has shown that people who read text on a tablet before bed don't sleep as well as those who read a traditional book (abstract).
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Study: Light-Emitting Screens Before Bedtime Disrupt Sleep More

Study: Light-Emitting Screens Before Bedtime Disrupt Sleep

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  • At a guess . . . (Score:5, Insightful)

    by mmell ( 832646 ) on Tuesday December 23, 2014 @01:20AM (#48657933)
    The amount of light entering the eye and stimulating the optic nerve is higher for the tablet. More light == more wakefulness. We're wired that way.

    • There's always the brightness control. I suspect most people set it too high.

      • Re: (Score:3)

        by SeaFox ( 739806 )

        I set mine waaay low when I'm reading late at night. Then again the room lights are also pretty dim, too. It's always surprising how dim it is if I try using it the next day in a fully lit room.

        • Re: (Score:2)

          by st0nes ( 1120305 )
          It Isn't the brightness of the light so much as the colour that's important [newscientist.com]. Blue light induces wakefulness, red light tells the brain it's time for sleep. If you can adjust the colour spectrum of your tablet, nudge it towards the red end of the spectrum and eliminate the blue and violet end.

      • Good luck finding devices that get dim enough, though; manufacturers have focused on making screens brighter for daytime use at the expense of nighttime usability.

        About the only devices I have that dim enough to tolerably use in a dark room are my Retina MBP and iPad, and even then I must use f.lux or light-on-dark color schemes to make it comfortable. I've tried screen filtering apps for Android, but they never seem to dim the soft keys and can cause unexpected battery drain.

        Oh, and don't get me started on

        • iphones seem to get plenty dim. I also second the thought that most people turn up the brightness. My friends, and their kids, have learned to max out the brightness every time they touch my phone.

      • Re:At a guess . . . (Score:5, Informative)

        by ProzacPatient ( 915544 ) on Tuesday December 23, 2014 @02:13AM (#48658141)
        Since most reading you'll do is black text on a white background I always go into accessibility settings and invert the screen so it will be white text on a black background which will emit significantly less light than the former.
        • Easy solution - get a screen made out of dark matter ... since it's 90% of the universe, what could possibly go wrong?

        • Re: (Score:2)

          by pepty ( 1976012 )
          For Windows: Negativescreen. I have it set to go to red text on a black background or go back to normal when I hit alt-win-v. It' much harder to get a useful setting on my tablet.

      • Re: (Score:2, Interesting)

        by Anonymous Coward

        There's always the brightness control. I suspect most people set it too high.

        No. That has much less to do with it than the frequency of the light. There is specific blue wavelength that triggers circadian rhythm. Essentially, if you are looking at a screen before bed, you are screwed. (and this seems to include me too)

        220V incandescent in a 120V plug tends to produce the light you need to get to sleep. So if you want to read, get a 40W 240V bulb on ebay from China, and use it in your 120V light fixture. It will be a dim, orange 10W bulb, but more than enough to read by. And doesn't

        • I've made a few "sleep light" things. Nothing complex, one is four blue florecent bulbs all plugged into the outlet-to-plug recepticals. This I can take and plug into whatever room I'm in when I'm trying to wake up. Not just by itself but in addition to the other lights. It's pretty bright and I think it's working. In the bedroom I've got red lights under the bed, and blacked out everything else I can find. I work 10 and 12hr shifts and it REALLY has been helping my sleep cycles.

          LED's aren't terribl

        • A better idea is to get a red led bulb off ebay. Save electricty and sleep better.

    • It's about light at the blue wavelength - the intensity obviously plays a part, but the wavelength is the primary cause. When the optical nerve receives EM at this wavelength the brain tells the pineal gland to not produce melatonin.

      • How do you think the pineal gland reacted due to inputs conveying this scheme [codinghorror.com]?

        Double shot of espresso?

      • Re: (Score:2)

        by hey! ( 33014 )

        I actually use yellow tinted goggles after 6PM this time of year. The sunlight is so short and weak this time of year my sleep schedule gets totally messed up. When that happens in the summer I just get up in the middle of the night and work until bedtime, but that doesn't work here in December because there's not enough light during the day to get synced up.

        So I try to go outdoors every day for an hour around noon, particularly if its overcast. And I wear those stupid goggles after 6PM, which is a PITA

    • The amount of light entering the eye and stimulating the optic nerve is higher for the tablet. More light == more wakefulness. We're wired that way.

      You'd be wrong. This is old news, it's something in the blue spectrum that causes the disruption. My parents already have a film on their glasses which filters out the light - they've been bugging me to get it for months.

      • It would be nice if they would build that into the screen. It doesn't need to be a lowpass, a notch would work fine without mangling the perceived colors.

    • I'm sure this was also reported years ago with TVs being an issue for sleeping, something about blue light being a disrupter

    • It's the colour of the light, more than its brightness. Blue light inhibits melatonin production, increasing wakefulness. Red light's ok at night, blue light's not.

      • Re: (Score:2)

        by arth1 ( 260657 )

        It's also the spectrum. It doesn't matter if the light is marked with a "warm" temperature, if it's really a mix of cold and warms with more warms. Light doesn't blend - our brain tricks us into thinking it's warm, filling in the blanks.

        To get broad continuous spectrum light, you need incandescent bulbs or halogen lights - even the best fluorescent and LED lamps don't exceed much more than a 80% color rendering index.

        So a book or an e-ink device without LED sidelight is what you want. I use warm halogen

    • Comment removed based on user account deletion

  • I had this problem, then I got f.lux. (Score:5, Informative)

    by pushing-robot ( 1037830 ) on Tuesday December 23, 2014 @01:25AM (#48657965)

    Just get f.lux. [justgetflux.com]

    • Re:I had this problem, then I got f.lux. (Score:4, Interesting)

      by carlhaagen ( 1021273 ) on Tuesday December 23, 2014 @01:41AM (#48658019)
      Same. I'm on 3200K during evening, 3000K before bed. Using the laptop before bedtime no longer affects my sleep, not even the least. The problem with blue light preventing melatonin production is long gone.

    • This. It helps immensely helped with keeping my sleep cycle consistent. There's also Lux for Android (https://play.google.com/store/apps/details?id=com.vito.lux&hl=en) which was very helpful too

    • Re:I had this problem, then I got f.lux. (Score:5, Informative)

      by drinkypoo ( 153816 ) <drink@hyperlogos.org> on Tuesday December 23, 2014 @08:19AM (#48659131) Homepage Journal

      Or for Android, since the summary implies mobile devices, there's Twilight [google.com].

      Or for Unix, since this is slashdot you fucking savage, Redshift [jonls.dk].

      On Unix, sadly, only Adobe Flash player detects color corrections and plays your video in proper color. Neither Google nor Mozilla have figured this out for flash video, either. Also, Flash player is the only video player which properly suppresses the screensaver on Linux. What year is it?

      • What year is it?

        Not the year of Linux on the desktop, apparently.

      • Re: (Score:2)

        by rdnetto ( 955205 )

        On Unix, sadly, only Adobe Flash player detects color corrections and plays your video in proper color. Neither Google nor Mozilla have figured this out for flash video, either.

        Strictly speaking, wouldn't you want the video to be in the adjusted colour? Most of my late night PC usage is watching video, and I don't even notice the change anymore. (It helps that Redshift gradually changes the colour temp.) That said, I found it made a huge difference to my sleeping patterns.

        • Strictly speaking, wouldn't you want the video to be in the adjusted colour?

          No. I want it to be in corrected but not adjusted color. It gets hard to see some stuff in some video otherwise. It probably ought to be a config flag, though.

  • Next on Bennett Haselton's Blog (Score:2, Informative)

    by Anonymous Coward

    "The math behind news reporting obvious,primordially old fact" Subtitle: "Algorithmic inspections into primordial facts: Case study: My own experience glimpsing into the cosmos thru words, heavenly turquoise light bathing my retinas in sweet abyss, long into the night, of wordy, frequent contributions".

  • Posted at 12:17AM.

  • By the time the light affects you, there will be a different display technology in use that doesn't pose the same alleged health risk

    • I'm not sure what vague risk you are referring to, but I don't think it has much of anything to do with the effect observed here.
  • that's a really good marketing slogan. Soulskill should copywrite it.

  • The blue light decreases melatonin production. Set your device to display amber on black and dim the room's lights. If you're extra sensitive to it like me, get yourself a pair of blue-blocking glasses.

  • This information was making the rounds 1-2 years ago. Seems some submitters are way behind in their reading.

  • Just get f.lux! (Score:5, Informative)

    by Radak ( 126696 ) on Tuesday December 23, 2014 @02:09AM (#48658129) Journal
    I use f.lux [justgetflux.com] on my MacBook and it's great (also available for Windows and Linux, but I haven't tried those versions). It adjusts the colour temperature of the screen, using your location and the time of day, to match the colour temperature of the natural light of that time of day. I have noticed a significant difference in the quality of my sleep since I started using it. Plus, whenever I happen to get up during the night and want use the computer for something, I'm not blinded by the screen.

    • Re: (Score:3)

      by jafac ( 1449 )

      just a word about this program - sometimes it gets flagged as spyware. I don't know if it's because f.lux has to know your location (in order to time the local sunset) - or if there's something else going on. There are some other programs. There is g.lux, and redshift, for starters.

      • Re:Just get f.lux! (Score:4, Informative)

        by Radak ( 126696 ) on Tuesday December 23, 2014 @04:07AM (#48658465) Journal

        I can't speak for the Windows and Linux versions, but I know from Little Snitch that the Mac version attempts to talk to port 443 on their webserver when it starts up, presumably for an update check. Additionally, it attempts to contact doubleclick.net and googleapis.com when you search for location. I just block all this traffic and haven't seen any adverse effects.

        Thanks for the pointers to g.lux and redshift. I'll check those out and see if they offer anything better for me.

    • What if you don't habitually use your computer/tablet outdoors?

      • Re: (Score:3)

        by Radak ( 126696 )

        f.lux isn't designed for outdoor use (although there's no reason you couldn't use it there). The idea is that the light coming off your screen matches the colour temperature of the natural light you'd be receiving if you were outdoors (and whatever might be coming through your windows), so that your brain's neurochemistry (melatonin in particular) matches what it should be doing at that time of day, helping you maintain a natural circadian rhythm, which it seems to accomplish in spades.

  • 12 people is really small for a study imo. I think there might be something to the idea, but the study seems lacking.

    There's so many variables that a much larger pool would be helpful.

    Are these 12 all regular bedtime readers? Which ones regularly read with an ipad/kindle vs. paper book? Are these 12 normally good sleepers or not? Why did they make them read for 4 hours (personally, that's much longer than anyone I know of reads before falling asleep)? I dunno too much left out of the study.

  • Reading books on an LCD device if fucking stupid anyway. Use e-ink, it is better for almost all books except certain technical ones (which mostly aren't that great as bedtime reading anyway).

  • Seems like common sense, biologically. More directed lights and more intense lights hitting an eyeball probably tricks the mind into wakefulness; less directed or less intense lights is more conducive to sleep behaviour. Not all that surprising. Also, this study can't be entirely conclusive with only 12 subjects being tested... I'm just going to go "meh" for now.

  • Misleading summary/abstract (Score:3)

    by reve_etrange ( 2377702 ) on Tuesday December 23, 2014 @04:25AM (#48658505)
    They used iPads, so this paper isn't really about e-readers in general, just tablets.
  • Causes the body to suspend production of the sleepiness stuff. Or something like that. There's a way to change the screen color: https://justgetflux.com/ [justgetflux.com]

  • If I read something at full brightness on my laptop I won't fall asleep either. Conversely, if I reduce the brightness to minimum over a minute or two I'll fall asleep soon.

  • In Other News... (Score:5, Insightful)

    by Kuroji ( 990107 ) <kuroji@gmail.com> on Tuesday December 23, 2014 @06:36AM (#48658819)

    Related studies have found that the main reason light-emitting screens keep people from sleeping is because they don't ever fucking shut them off and the next thing they know it's 5:36 in the bloody morning!

  • Yeah me too (Score:3)

    by codeButcher ( 223668 ) on Tuesday December 23, 2014 @06:46AM (#48658849)

    I sometimes work into the night ("flow"). Other times I read a while in bed on my (big-screen) phone. I use f.lux on the computer, Bluelight Filter on android - other apps have been mentioned.

    The science seems to be fairly well understood for a number of years, long enough to develop these apps. See e.g. http://en.wikipedia.org/wiki/M... [wikipedia.org] for pointers, http://en.wikipedia.org/wiki/C... [wikipedia.org] may also be of interest (other effects than light on sleep).

  • You could just knock yourself unconscious with it.

    • Re: (Score:2)

      by Chrisq ( 894406 )

      You could just knock yourself unconscious with it.

      Or watch porn until you exhaust yourself

  • Taking a sleeping tablet to bed doesn't have the same effect apparently.
  • Its a shame it doesn't comment on front-lit e-ink displays (e.g. paperwhite). I would think these would be better than backlit displays, but not as good as unlit displays or books,

  • I enjoy the Kindle app on my iPad and read in bed every night before I go to sleep. Occasionally, I fall asleep while reading. Sometimes I read paper books too. I have noticed no difference in my sleep patterns, and I sleep quite satisfactorily.

    A couple of things come to mind. First, even when I read with my tablet, I still have the lamp on, just like I would with a paper book. That may make a difference. Second, is it possible that the content is different when using a tablet for most people. That i

  • a study has shown that people who read text on a tablet before bed are douchebags

  • Four Hours of Reading? (Score:3)

    by shambalagoon ( 714768 ) on Tuesday December 23, 2014 @12:18PM (#48660279) Homepage

    In the study the people read for four hours before sleeping. I love reading as much as anybody, but is this a realistic scenario? I'd be more interested to see the sleep disruption from 30 minutes to an hour of reading on light-emitting screens before sleeping.

    • Re: (Score:3)

      by PPH ( 736903 )

      Four hours of H.P. Lovecraft will keep anyone awake.

    • You might only use the tablet for 30-60 minutes, but myself, most of the previous 4 hours were already spent looking into various bright screens (a little better now with f.lux).
  • We won a Fire in a raffle, so I put the next book of a series I've been reading on it. It works fine during the day and on the can, but it's awful right before bed. Even on its lowest brightness setting, it feels like staring into the sun (probably why it chews through battery so fast). Anybody know how to get Kindle books on an old Sony e-reader? Yay LCD!

  • Can anyone recommend an Android app that can filter the screen by either dimming it past what it normally does with the built-in settings, or removes certain light frequencies?

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