Home » In the Magazine » How Device Use Affects Vision

How Device Use Affects Vision

How Device Use Affects VisionAs people of all ages are spending more hours focused on digital screens, their eyes are getting an exhausting endurance workout.  In addition to watching TV, many adolescents and adults stare at computer screens for hours each day, utilize e-books and iPads, and scan endless text messages on hand-held devices and cell phones.  On any given day, exposure to screens can total approximately 8.5 hours.  According to research by The American Optometric Association, approximately 65 percent of adults spend 7 or more hours in front of a computer every day.  Statistics also show 83 percent of children between the ages of 10 and 17 use a digital device for at least three hours each day.  This year alone, it is estimated that nearly 60 million children will use a computer or digital device for multiple hours a day, which does not include TV time or use of a video game system.

Using digital devices, requires eye muscles to focus at a near range, which can be fatiguing.  Digital eye strain is a group of eye- and vision-related problems that are due to extended computer or digital device use.  Digital eye strain sufferers routinely exhibit redness and dryness due to decreased blinking; blurry vision due to screen glare; headache from prolonged eye strain; and neck/shoulder/back pain that is caused by poor posture and sub-optimal screen position.  One of the more common symptoms, dryness, is caused by reduced blinking while staring at screens.  A person’s blink rate averages 15 to 20 blinks per minute – can decrease by up to half when eyes are fixated on a screen.  For example, when staring without blinking, eye moisture evaporates very quickly.  Dry spots and blurred vision can occur, causing redness and pain.  As with the range of symptoms, the severity can be widespread as well.  Some people may have little to no complaints, while others may consider digital eye strain to be disabling.

Although digital eye strain is not a lasting condition, it is very problematic for those it affects, especially in today’s electronic world.  Typically, the effects increase throughout the day while electronic usage is highest and then wane once computer use is discontinued.  According to American Optometric Association statistics, 80 percent of what we learn is through our eyes, which can have a dramatic influence on children as well as adults who suffer from digital eye strain.  It is estimated that as many as one in four students have visual impairment problems, and 20 percent of middle and high school students have difficulty seeing the board in school.

Similar to other muscles in the body, the eyes need a varied “workout” and some respite from prolonged strain.  The 20-20-20 rule is recommended by the National Eye Institute.  Every 20 minutes that you are on a computer or a mobile device, look away from the computer at an object 20 feet away or further for 20 seconds or more.  This change in focus will allow those eye muscles to relax.   In addition to taking breaks from focus on digital screens, optometrists recommend adjusting light exposure to help with eye strain, both indoors and outdoors.  Contrary to popular opinion, more indoor light may actually be worse for reading, when it is on a screen.  Too much light competing with the device’s light creates glare.  And a bright, white background also is worse than a cooler, gray tone.  Getting enough outdoor/natural light also is critical to helping eye muscles develop and stay healthy.  When children are not exposed to enough natural light, the eyes might become more near-sighted.

Most digital screens are backlit and emit blue light, or high-energy visible (HEV) light wavelengths.  Blue light is part of the full light spectrum, which means we are exposed to it by the sun every day.  However, increased exposure can cause irritation and possibly long-term damage to the retina.  In addition, nighttime exposure to that light, which is emitted at high levels by smartphones, tablets, laptops and other LED screens, suppresses production of the sleep hormone melatonin, causing an artificial feeling of wakefulness and disrupting sleep patterns, which can add to eye strain.  When melatonin levels and sleep cycles are imbalanced, there is increased risk for a wide range of ailments, from depression to cancer.  We cannot avoid smartphones, computers, and tablets all the time, but exposure should be limited, especially at night before bed.

www.lmhealth.org