Nearly three years into the COVID-19 pandemic, screen usage has increased exponentially, especially among children. The average amount of time children spend staring at screens has risen 52 percent since the beginning of the pandemic, according to a recent study published in JAMA Pediatrics.
Even before the pandemic, the average American adult spent about 3 hours and 30 minutes a day using mobile internet in 2019, an increase of about 20 minutes from a year earlier, according to measurement company Zenith. (You probably already know this if you get one of those “screen time usage” reports weekly from your phone.)
Smartphones are an integral part of our lives, but what effect does all this scrolling and staring have on our brains? What can we do to protect ourselves and our children?
Here’s what we know.
Smartphones May Affect How We Think
Although there is not yet clear evidence that smartphones have a long-term negative effect on the brain, health experts are concerned that excessive use can be harmful—especially to children whose brains are not yet fully developed.
For example, research has shown that smartphones may adversely affect cognition (but more study is needed to understand the connection). Cognition is the process of acquiring and applying knowledge through thought, experiences and the senses.
A study in the Journal of the Association for Consumer Research found that cognitive capacity was significantly reduced whenever a smartphone is within reach, even when the phone is off.
With smartphones, you no longer need to memorize a phone number or find your way around town using a map—your smartphone does these things for you. Research shows this overreliance on your phone can lead to mental laziness.
Modern connectedness also could be rewiring our brains to constantly crave instant gratification.
“Social media, in my view, provides the user with inconsistent positive reinforcement, similar to gambling. When the user posts a message, the number of likes serve as a reward, and the chance of more likes increases with one more scroll or one more message. The user is not always rewarded with likes and positive responses, but these are quite satisfying when occurring. In fact, the user may unconsciously change their views to appease friends who provide likes, and select a friend population with shared values,” says UNC Health neurologist Jorge L. Almodóvar-Suárez, MD.
Smartphones May Affect How We See
Since the beginning of the pandemic, there has been an increase in children with myopia (nearsightedness), says UNC Health neuro-ophthalmologist Maja Kostic, MD, PhD.
Nearsightedness is an eye condition in which people can view objects up close clearly, but things farther away appear blurry.
“We are currently doing studies to measure the effect of smartphone usage on children’s long-distance vision,” Dr. Kostic says. “If kids are looking at phones at a near distance for long hours without any break, then we think this could lead to more and more progression with myopia.”
Smartphones Can Impair Social and Emotional Skills
The more time you spend looking at a screen, the less time you spend interacting in person with others. This makes it more difficult to establish interpersonal connections and strong relationships, which are important for mental health and the health of the community at large.
Using screens to zone out or decompress is fine in moderation, but there can be a negative effect if excessive.
“Anything that is done out of moderation is cause for concern,” says UNC Health pediatric and adult neurosurgeon Carolyn Quinsey, MD. “For children, they are learning early in life to engage in passive activities instead of being actively engaged, which can become a habit as they grow older.”
That lack of face-to-face interaction can lead to depression. Health experts are also concerned that excessive social media use—especially among teens—can lead to depression and anxiety.
“We know that social media can be linked to depression and anxiety,” Dr. Almodóvar-Suárez says. “When we go into social media and post, we’re posting a manufactured life—picking the best pictures of ourselves or the nicest picture from our trip. We’re not showing an ugly part of the trip, like a four-hour bus ride or an unflattering picture. The problem is that when we see that from other people, we start to question why we can’t be having that same experience. We feel like something is missing.”
Concern about the long-term effects of technology and social media use on teen social and emotional development was the impetus for a new research center at the University of North Carolina at Chapel Hill that will study the impact of technology and social media on adolescent brains.
How to Protect Your Brain from Your Phone
You don’t have to swear off your phone completely to improve your brain health. The important thing is to be aware of how you use your phone and other devices and to prioritize other activities and in-person interactions whenever possible.
“The first thing adults or children can do is create some awareness around it. A lot of people aren’t aware of how much time they’re spending on a particular activity that involves a screen,” Dr. Quinsey says.
Most smartphones allow you to track your average screen time hours. Pay attention to how much time you are spending.
“If you feel like that’s a problem for you or your child, make adjustments,” Dr. Quinsey says.
“We can be more purposeful about the time that we’re using a screen, rather than it being so habitual.”
Some people find it helpful to delete social media apps from their phone or to download software that limits the time they’re permitted on a particular site. Others designate hours of the day “phone-free” to protect family time. It can be empowering to trade screen time for reading a book or working on a hobby.
As you scale back your phone time, the increase in your mental clarity or mental health might be motivation enough to keep it up.
To avoid harmful side effects of screen usage on the eyes, adults and children should practice “screen hygiene,” a set of best practices for using screens. To start, hold digital media at least 18 to 25 inches from your face.
Also, practice the 20/20/20 rule: Every 20 minutes, look up from your device at something 20 feet ahead for 20 seconds. This relaxes your eyes. For example, look out the window between rounds of Candy Crush or after a chapter or two of an e-book.
Forgoing any use of technology is not realistic, but it’s important to set boundaries and time limits—your brain will thank you.
Talk to your doctor if you have concerns about the effect your devices are having on your brain. If you need a doctor, find one near you.