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How screens affect children and adolescents

While the notion is that greater screen time is always bad, studies indicate that that it might not be so clear cut.

Last month, we featured a special gadget in the Digit magazine – the IRL glasses. These were glasses that can block out screens for you without blocking out anything else. While the mechanism behind it might be interesting, it brought us to wonder how significant the effect of screens around us is – especially on the younger members of our society. With smartphones, televisions and other forms of digital screens becoming ubiquitous and accessible to all age groups, children and adolescents are obviously no exceptions. There’s been a lot of attention on how increasing usage of gadgets with screens has been affecting various aspects of the lives of non-adults – including academic studies in a large number. So, by now, we should be pretty clear on whether screens are good or bad for the young ones, right? Turns out, it’s more complicated than that.


 How many times have you been told, or heard, that staring at smartphones before or while going to bed ruins your sleep cycle? It’s hard to avoid this piece of information especially when device and app manufacturers are introducing things like Dark Mode, Reading Mode, Night Light etc. to reduce the amount of blue light that our eyes are subjected to in the fag end of the day. Things are no different when it comes to children, and the general consensus seems to be that increased screen time is bad for sleep, more so for children. There are studies that back this consensus. One conducted by researchers from San Diego State University and Iowa State University, involving the analysis of data from more than 350k adolescents, shows a 16-17% increase in likeliness of short-sleep duration over a period of time where screen time also increased significantly (dgit.in/STStudy1). The study was able to draw a clear “exposure-response” relationship between the two, with other factors affecting sleep time relatively constant or on a downward curve. 

Effects of screen time on sleep might have been exaggerated 

However, there are studies that point in a slightly different direction as well. A recently concluded study by the University of Oxford offers enough evidence to the contrary of the generally accepted notion that more screen time leads to significantly shorter sleep durations. While the sample size of this study was smaller at around 50k, this sample was taken with the objective in consideration. The author of the study, published in the Journal of Pediatrics, Professor Andrew Przybylski states that the previous studies have wrongly either used small sample sizes or decided samples after obtaining the data, which could have led to misleading results. He also acknowledges that most of the data for such studies are obtained by consulting parents, which makes the data imperfect. The Oxford study accommodates for the variables by “adjusted for child-, caregiver-, household-, and community-level covariates”. What this means is that the study accounted for things like the age, sex and ethnicity of the children, the education level and the financial situation of the immediate caregivers and the family involved, the availability and affordance of alternative activities for children in the community they are a part of and other such external factors that also impact the duration children spend with a screen. The results of the study do point to a correlation between increased screen time and lesser sleep – one that is quite insignificant when compared to other factors. For instance, the average sleep duration of a tech abstaining teen was found to be only a half hour more than that of one devoted to screens for about eight hours a day. Other factors, such as regular bedtime discipline, earlier start to school days and more were found to be way more significant in affecting sleep duration. It does need to be said that the author has also indicated that future studies need to focus on data with a lower degree of imperfection to provide better insights into the real-world impact of screen time on the sleep cycles of non-adults. You can read the full study here: dgit.in/STStudy2.  

Psychological and physical effects

 While sleep is one of the first things that comes to mind when discussing the impact of screen time on non-adults, there are other areas impacted as well. The ubiquity of screens has made them significant influencers on the mental state of children and adolescents. Parents and caregivers are increasingly inclined to use videos and apps on smartphones and other smart devices to engage and educate non-adults. The impact of this has also been analysed by several studies, and the findings are more conclusive than those pertaining to sleep duration. A study conducted earlier this year has found that increased screen time leads to lower mental well being among 2 to 17 year-olds around us. While up to 1hr of screen time proved inconclusive, anything more than that led to adverse effects like “less curiosity, lower self-control, more distractibility, more difficulty making friends, less emotional stability, being more difficult to care for, and inability to finish tasks”, leading to a poorer overall state of mental health. Heavy users (more than 7 hours a day) are even identified to be twice as likely to be diagnosed with depression, anxiety and seek psychological help. This association was found to be more prominent in adolescents than younger children. Other studies in this area have reached similar results. 

Shows like Sesame Street have been found to have a positive effect on the learning of children 

Things get interesting when we focus on younger children. Some studies indicate that there is a right amount of screen time that can actually have a positive effect on the cognitive abilities of children. In fact, there’s enough evidence to establish that the factors affecting the mental health of children based on screen time are significantly more complex than those of sleep. For instance, productive content for children is usually designed keeping in mind the translation of skills from the two-dimensional format that screens can provide to the three-dimensional world around us, especially with the assistance of parents or immediate caregivers. While the well-structured material has been helpful, an analysis of most of the apps and programs easily available online shows that these pay little attention to established and tested curriculums, or do not really encourage the learning process as much as seeming engaging to the child. In such cases, increases screen time definitely has the adverse effects mentioned earlier. The impact is certainly not limited to the mind. Increased screen time often directly points to a sedentary lifestyle, which leads to conditions like obesity among other things. A study of 2-year-olds found that BMI increased for every hour per week of media consumed. Certain factors like food advertising and distraction during eating (which affects the perception of satiety cues) are also held responsible. 


 While the real world impact of screen time has been varying on the non-adults that have been studied, there’s no real confusion towards the fact that there is a negative impact, however significant or insignificant it might be. As many of these studies have shown, the need of the hour is to conduct detailed research involving cost-benefit analysis of screen time that goes down to the minutest level possible when it comes to accounting for variables in the study data. We’re sure that we can pull that off, our future is at stake, after all! 


Arnab Mukherjee

Arnab Mukherjee

A former tech-support desk jockey, you can find this individual delving deep into all things tech, fiction and food. Calling his sense of humour merely terrible would be a much better joke than what he usually makes.