Landing : Athabascau University

Teens unlikely to be harmed by moderate digital screen use

The results of quite a large study (120,000 participants) appear to show that 'digital' screen time, on average, correlates with increased well-being in teenagers up to a certain point, after which the correlation is, on average, mildly negative (but not remotely as bad as, say, skipping breakfast). There is a mostly implicit assumption, or at least speculation, that the effects are in some way caused by use of digital screens, though I don't see strong signs of any significant attempts to show that in this study.

While this accords with common sense - if not with the beliefs of a surprising number of otherwise quite smart people - I am always highly sceptical of studies that average out behaviour, especially for something as remarkably vague as engaging with technologies that are related only insofar as they involve a screen. This is especially the case given that screens themselves are incredibly diverse - there's a world of difference between the screens of an e-ink e-reader, a laptop, and a plasma TV, for instance, quite apart from the infinite range of possible different ways of using them, devices to which they can be attached, and activities that they can support. It's a bit like doing a study to identify whether wheels or transistors affect well-being. It ain't what you do, it's the way that you do it. The researchers seem aware of this. As they rightly say:

"In future work, researchers should look more closely at how specific affordances intrinsic to digital technologies relate to benefits at various levels of engagement, while systematically analyzing what is being displaced or amplified," Przybylski and Weinstein conclude. 

Note, though, the implied belief that there are effects to analyze. This remains to be shown. 


  • I agree that screen types and readability are issues, just as a hardcopy versus bad photocopy.

    Your commentary prompted my questions:

    • Does reading a reflected or refracted light surface make a difference in well being.
    • Which is less disturbing - a digital billboard or a non-electronic one?

    Steve Swettenham January 19, 2017 - 3:29am

  • Jon,

    I appreciate your sharing this and encouraging us to look beyond the obvious.

    My wife is found of quoting "research" that any interruption to one's attention requires 20 minutes for us to refocus. I also told her that this would not serve much of a beneficial evolutionary purpose.

    Gerald Ardito January 23, 2017 - 4:03pm

  • @Steve - indeed, light source and brightness makes a lot of difference.  I am still pondering whether the side-lit (reflective) light of a Kindle Voyage is any better than a backlit tablet. On the whole, I think it is. It feels more comfortable, at any rate, especially as the Kindle Voyage is very good at adapting to ambient light levels. On a spectrum of comfort it is superior to shining even a dim light directly in my face. I had a clip-on flashlight on an older e-book reader which lacked its own illumination, which seemed pretty similar but felt a bit more awkward and a bit less comfortable to use. It was still more comfortable than the same arrangement on a p-book, though, especially as the curvature of the pages made the lighting uneven. It ain't what you do, it's the way that you do it!

    @Gerald - the research is ongoing and equivocal on such things, but there has certainly been some: I mentioned some of it a while back in my post on The cost of time. I wonder whether distraction has been a problem for humans for long enough for us to have evolved much of a defence against it? There's a plausible hypothesis to be made that It didn't matter much in the savannas and jungles: at least that it was either a good thing to be distracted by and switch attention to more salient events (the unexpected might rightly demand our prolonged attention), or that the cognitive costs of fast recovery and multitasking outweighed the practical benefits. I can see arguments both ways, though. 


    Jon Dron January 23, 2017 - 5:10pm

  • "It ain't what you do, it's the way that you do it!"

    Do you mean that the way an e-reader device is used in the environment will be a more important consideration for comfortability (i.e., eye strain) than what e-reader device is used?

    Steve Swettenham January 24, 2017 - 2:58pm

  • @Steve - not so much, although that is probably something to factor into any study. I mean that it is not important that it is an e-reader, but it is important how it is designed.

    There are way more current and possible designs for e-readers than for p-readers (notwithstanding - or perhaps because of  - thousands of years of evolution) and, if any of the design factors make a difference (and I am sure most do), it is always possible to design them differently. It's significantly more complex than that, too, because of the rich interplay between design elements.

    It's exactly the same issue as comparing e-learning and p-learning and expecting to find some universal qualitative difference in learning. It's a bit like saying all paintings are better than all drawings, or all blues music is better than all classical music. Makes no sense. We can probably fairly reliably find out how one particular design configuration compares with one other design configuration, and we can probably find out that some things (e.g. shining 100 lumens of light directly into someone's eyes) are (almost) always a bad idea for at least some kinds of activity, and we might even be able to discern some generalizable patterns that have held in the past but, unless they have held 100% of the time across all contexts, there is no reason to suppose that, given our capacity to alter the design, they will hold in the future. Of course, if we do find something is a universal problem, then the next step is to look for a solution. But it is no more sensible to investigate whether learning (or reading, or art) is better (or worse) with or without electronic media than it is to investigate whether it is better (or worse) with or without glue.

    Jon Dron January 24, 2017 - 4:56pm

  • Based on your noting that there is a difference between direct and indirect light to the eye, would it be useful to research human interactions to visual displays?  In example, a cinema display of reflected light is a different interface to the eyes, from a digital display screen of the same size (your flashlight note). The majority of humans (with 1B+ smartphones) have adapted to digital displays. This adaptation to non-natural/virtual direct light has no biophysical change? or has exposure to such technologies been too short in our species timeline (or human lifetime) to investigate?

    Steve Swettenham January 25, 2017 - 3:03am

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