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Study: Light-Emitting Screens Before Bedtime Disrupt Sleep

Posted by Soulskill on 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).

12 of 179 comments (clear)

  1. At a guess . . . by mmell · · Score: 4, Insightful

    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.

    1. Re:At a guess . . . by ProzacPatient · · Score: 4, Informative

      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.

    2. Re:At a guess . . . by Cinnamon+Beige · · Score: 4, Informative

      I went and poked around medical journal databases. MedlinePlus has little, though it confirms the dosage recommendations, while a bit of work via PubMed located this study which I think may be the correct citation. Its PubMed listing seems to indicate that it's not the sole possibility, though, as do its references.

  2. I had this problem, then I got f.lux. by pushing-robot · · Score: 5, Informative

    Just get f.lux.

    --
    How can I believe you when you tell me what I don't want to hear?
    1. Re:I had this problem, then I got f.lux. by carlhaagen · · Score: 3, Interesting

      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.

    2. Re:I had this problem, then I got f.lux. by disambiguated · · Score: 4, Informative

      when things are dark, and you need more light, it dims things.

      Exactly the opposite: when things are dark, your pupils dilate and you need less light. Do you turn your smartphone brightness down in bright sunlight?

      But brightness isn't the point -- color temperature is. I haven't read the documentation; the software is too simple and easy for that, but the homepage describes what it does. Flux lowers the color temperature at night, which interferes less with sleep. I also find it much more pleasant.

    3. Re:I had this problem, then I got f.lux. by drinkypoo · · Score: 4, Informative

      Or for Android, since the summary implies mobile devices, there's Twilight.

      Or for Unix, since this is slashdot you fucking savage, Redshift.

      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?

      --
      "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
  3. Re:What about... by mark-t · · Score: 3, Informative

    1. e-paper has a positively abysmal screen update time

    I use my tablet a lot for reading highly technical articles, and I often end up flipping back and forth between different pages of the text while I am reading, usually between a page with a figure or code listing and an explanation that follows or precedes it. I'd rather not add an easily perceptible delay between the time that I slide my finger one way or the other to advance or go back a page and the time it takes to actually show it.

    2. e-paper's full color support is poor.

    Many of the articles that I read come with slides which I also view on the tablet, and color is very useful at conveying information. Some progress has been made on this front, but for most practical purposes, epaper is generally monochrome.

    But certainly, if they ever get around to making a non-emissive display technology with a fast enough screen update time that you can't notice any delay between your actions and when the screen update is complete, and they provide respectable full color support, I'll be all over it. The only reason I use a tablet instead of hard copy at all is portability.

    --
    File under 'M' for 'Manic ranting'
  4. Just get f.lux! by Radak · · Score: 4, Informative

    I use f.lux 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.

    1. Re:Just get f.lux! by Radak · · Score: 3, Informative

      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.

  5. E-Reader does work for some technical stuff ... by perpenso · · Score: 5, Interesting

    I understand what you are getting at. I'll use an iPad Retina or laptop during the day to check technical books, reference manuals and other documentation.

    However when reading at night its generally a more traditional book (history, sci fi, etc) on a Kindle PaperWhite, in my opinion, its equivalent to a paper book but more convenient. I feel it is a better experience even when compared to the lightest color tablets. Certainly it will vary from one technical field to another but I've had surprisingly good results when reading programming and software development books on the PaperWhite, not as good as a higher resolution color tablet but better than I expected and acceptable with respect to the illustrations and diagrams and such. Then again I haven't tried something like the latest edition of Foley and van Dam (a computer graphics text).

    I see the refresh you speak of but its less than turning a paper page of a real book. As for the time you believe you are saving, maybe the faster refresh of a color tablet is not a win once you consider the sleep disruption and also the lowered productivity that results?

  6. In Other News... by Kuroji · · Score: 4, Insightful

    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!