A study conducted on Australian schoolchildren found that symptoms of dry eye worsened after one hour of smartphone gaming. Their blink rate significantly decreased, dropping from 21 blinks per minute to 9. Additionally, the interval between blinks extended from 3 seconds to just under 9 seconds within the first minute of gaming. The research was published in the journal Eye.
In the early decades of the 21st century, the prevalence of digital device usage among children surged dramatically. Among these devices, smartphones are the most widely used. In the United States, 83% of children own a smartphone by the age of 15, a trend that is mirrored globally. Children often spend several hours on digital devices, causing concern among medical professionals.
Excessive screen time on digital devices has been associated with adverse health and mental health outcomes in children. Research indicates that prolonged screen viewing is linked to a faster progression of myopia (nearsightedness) in both children and adolescents. Additionally, the likelihood of experiencing eye fatigue and strain increases after more than two hours of smartphone use.
Study author Ngozi Charity Chidi-Egboka and her colleagues wanted to examine the effect of one hour of smartphone use on blinking, dry eye symptoms, and tear film indices in school children. The tear film is a thin layer of fluid that covers the surface of the eye, providing lubrication, protection, and a smooth optical surface for clear vision. Various measurements used to assess the stability, quantity, and quality of the tear film are called tear film indices.
The study included 36 children aged between 6 and 15 years, recruited from the main campus of the University of New South Wales in Sydney, Australia, and its surrounding community, with a female majority of 22 participants.
To participate in the study, children visited the researchers’ lab, where they were asked to play games on an iPhone 5 for an uninterrupted hour. The selected games were Despicable Me: Minion Rush and Racing Penguin. Before starting and during gameplay, participants wore a monocular eye tracking headset to monitor their blink rate. Additionally, researchers assessed tear film function before and after gameplay. Participants also completed three questionnaires to evaluate ocular symptoms: the Instant Ocular Symptoms Survey, The Symptoms Assessment in Dry Eye, and the Numerical Rating Scale (for eye symptoms).
Results showed that tear film function did not change during gameplay. After 1 hour of gaming, tear film function indicator values were more or less the same as they were at baseline. In contrast to this, ocular symptoms as measured by questionnaires became significantly worse.
Blink activity measurements showed that blink rates decreased strongly in the first minute of smartphone gaming relative to the values they had during the conversation with the researchers before the start of gaming. Before the start of the study, participants blinked roughly 21 times per minute, on average. During gaming, this rate was just under 9 blinks per minute.
The time interval between two blinks also increased, going from 3 seconds before the game to a bit less than 9 seconds within the first minute of gaming. It remained unchanged throughout the gaming period. Eye symptoms the children reported were not associated with blink speed.
“Smartphone use in children results in dry eye symptoms and immediate and sustained slowing of blinking, with no change in tear function evident up to one hour. Given the ubiquitous use of smartphones by children, future work should examine whether effects reported herein persist or get worse over a longer term causing cumulative damage to the ocular surface,” the study authors concluded.
The study sheds light on changes in eye behavior during smartphone gameplay. However, as authors note themselves, it remains unknown whether these effects are only temporary, disappearing as soon as gaming stops or if they persist. Also, the presented results do not allow any conclusions about long-term effects of smartphone use to be drawn.
The paper, “Smartphone gaming induces dry eye symptoms and reduces blinking in school-aged children,” was authored by Ngozi Charity Chidi-Egboka, Isabelle Jalbert, and Blanka Golebiowski.
