An experimental set-up showing the wearable eye tracking headset (Pupil Labs GmbH Berlin, Germany) during smartphone use. Image: UNSW
Smartphone gaming induces dry eye symptoms and reduces blinking in school-aged children, researchers at UNSW have found.
According to their research, published in Eye, the study participants’ blink rate per minute halved.
Associate Professors Isabelle Jalbert and Blanka Golebiowski and PhD candidate Ms Ngozi Charity Chidi-Egboka, all from School of Optometry and Vision Science at UNSW, studied children playing games on a smartphone continuously for one hour.
“Smartphone use by children is rising rapidly, but its ocular surface impact is unknown. This study examined the effect of smartphone use on blinking, symptoms, and tear function in children,” they wrote.
The study participants – 36 children aged six to 15 years (14 male, 22 female) – played two games continuously for one hour using an iPhone 5s.
Symptoms and tear film (lipid layer thickness, tear secretion, stability) were assessed before and after gaming.
Blink rate and interblink interval were measured in situ using an eye tracking headset, before (during conversation) and continuously throughout gaming.
Jalbert, Golebiowski and Chidi-Egboka examined symptoms and tear film changes using paired t-tests.
“Changes in blinking throughout one hour were examined using repeated measures ANOVA (analysis of variance), and post-hoc comparisons with Bonferroni correction,” the authors wrote.
“Associations between changes in blink parameters, ocular symptoms and tear film function were examined using Pearson bivariate correlation. All tests were two-tailed, and significance was established at p < 0.05.”
They found symptoms worsened following one hour smartphone gaming, but tear film remained unchanged. Blink rate reduced from 20.8 blinks per minute to 8.9 blinks per minute. Interblink interval increased from 2.9 seconds to 8.7 seconds within the first minute of gaming relative to baseline conversation, and this effect remained unchanged throughout one hour of gaming.
The researchers concluded their study – the first study in children to examine ocular symptoms, blink parameters in situ, and tear film indices following smartphone use – demonstrates the rapid impact of screen viewing on eye health in children.
“These findings can help to inform recommendations for use of digital devices, including smartphones, by children,” they said.
“Children may be at risk in the longer term of developing ocular surface disease and dry eye from excessive use of smartphones.”