By Shimon Herman, Staff Writer
“Don’t sit too close to the TV or you’re going to damage your eyes.”
This line has been repeated so many times that it’s practically engraved as common wisdom; no one would dare to question its validity. However, is there scientific evidence that gives this line any credibility?
One of the most magnificently complex organs in the body is the eye. The biological masterpiece has the ability to project images, detect colors and motions, and regulate light intake. Eyesight functions by directing light through the cornea and pupil, where the lens (a clear internal structure of the eye) focuses the light directly onto the retina (a unique tissue layer at the back of the eye). The exact spot where light hits the retina is crucial for correct vision. If light is focused right before or after the retina, our vision becomes blurred. As the retina is hit with light, special cells called photoreceptors turn the light into electrical signals. The brain turns these signals into the detailed images that we see.
Myopia, or short-sightedness, occurs when the eye is elongated, causing light to focus in front of the retina rather than directly on it. This results in distant objects appearing blurred or distorted.
Numerous researchers have tried to connect the amount of screen time that children are exposed to and the increasing cases of myopia. Many of these researchers have emphasized that it isn’t the screens themselves that primarily damage the eyes, rather it is how we interact with screens that affects our eyes.
The American Optometric Association suggests that the same potential risks that apply to people looking at computers all day also apply to those who spend considerable amounts of time reading or engaging in any other similar intense visual work. The eye undergoes a significant amount of stress when focusing on something up close as the eye’s lens remains in a contracted position for an extended period of time. Not having a chance to relax, the eye becomes weakened, leading to vision distortion. These blurry images send messages to your brain that lead to changes in the shape of the eye.
However, there are many studies that point to excessive screen time having a greater risk of eye damage than other forms of intense eye focus. In a study done by Johns Hopkins Medicine, it was found that people who focus on screens for too long are more prone to eye fatigue. This is due to the sharp decrease in blinking that occurs when looking at screens. Without blinking, the cornea becomes overly exposed to air and evaporation, which leads to worse vision. Dr. Akpek, a specialist in Corneal Diseases, explained, “Focusing too intensely on a screen can dry out your eyes, making reading harder. As reading becomes more difficult, you strain your eyes even more, which worsens your vision, creating a cycle.” Others have attributed the increased risk associated with screen time to factors such as glare, the angle of focus, and the irregular shapes on the screen, all of which contribute to added stress on the eyes.
Screen time is especially dangerous to young children whose eyes are in fragile years of development. All humans are born with hyperopic eyes (shorter eyes), which makes them long-sighted. Ideally, the eye goes through a process called emmetropization, where the eye stops growing upon reaching the normal length required for clear vision. However, when children are exposed to screens at young ages their eyes grow more than needed. Professor Bourne, Professor of Ophthalmology at the Vision and Eye Research Institute at Anglia Ruskin University, said, “Around half the global population is expected to have myopia by 2050… This research comes at a time when our children have been spending more time than ever looking at screens for long periods.”
Unfortunately, the average of over eight hours a day that young adults spend looking at screens is far greater than the recommended two hours. One solution that experts suggest to help prevent further eye damage is the 20-20-20 rule. Every 20 minutes spent using a screen, try to look away at something 20 feet away for 20 seconds. This is how long it takes for your eyes to reset and relax.
Additionally, there is strong evidence that suggests that outdoor activity during childhood is linked to better eye health. Although studies do not confirm that outdoor exposure alone can completely halt the progression of myopia, children who spend more time outside show significantly lower rates of its development.
There’s no question that we have benefited from the advancement of technology, but in a world with 18 million mobile devices, there is no escaping this issue. It is crucial that we work to find the right balance between the benefits and risks of screen time before the damage to our eyes becomes an irreversible consequence of our digital dependence.