The effects of screen time on children: The latest research parents should know

Screen time guidelines for babies, toddlers, kids and teens

As technological innovations like cellphones and video games have become ever more prevalent over the past few decades, young people have been spending more and more of their time immersed in these gadgets. And too much screen time can have a deleterious impact on the development of young minds and bodies.

While various agencies offer guidelines on how much screen time kids should encounter in a day, Dr. Michelle Yang, a CHOC resident, wanted to know why these recommendations are in place and how helpful they really are. She discussed her research at a recent lecture at CHOC titled “Effects of Screen Time on Children and Adolescents.”

While the impact of unfettered access is negative, there are circumstances when screen time can help a child learn certain skills. And a little time on a device can actually help improve a child’s mental health.

How has screen time use changed among youth?

Recommendations are one thing, but Dr. Yang also knows that many young people often spend more time online than ever before. Teens now spend an average of eight hours a day on screens, two hours more than in 2015.

Preteens (children aged 8 to 12 years) spend about 5 ½ hours daily on devices, up an hour from a decade earlier. That means that some young people spend half of their waking day in front of a screen. Usage jumped in 2019 just before the COVID-19 pandemic started to spread.

At least half of those hours are spent on the TV, not just on phones or tablets, Dr. Yang says, but the studies looked at various types of media.

“I think it’s really important to understand why we give the recommendations we do and what the reasoning for it is,” Dr. Yang says.

What are the screen time recommendations for children and teens?

So, what are the recommendations? According to the American Academy of Pediatrics (AAP) and the U.S. Centers for Disease Control (CDC), they are:

• Younger than 18 months: No screen time, except for video chatting with family and friends
• 18 to 24 months: Only high-quality educational media with parental engagement
• Ages 2 to 5 years: No more than one hour a day
• Age 5 years and older: No more than two hours a day, while engaging in conversation with a parent or family member about what is being viewed
• Pre-teens and teenagers: Varied effects on mental health, academic achievement, and social skills; importance of balancing screen time with physical activity and healthy habits.

Instead of children spending their days looking at monitors, the agencies suggest some simple age-appropriate alternatives: play a ballgame, ride a bike, do yard work, dance to some music, or take the dog for a walk.

What is the role of an adult’s presence during screen time?

Dr. Yang noted that limiting screen time is only part of the solution. It’s also important for adults to be active participants, especially for younger children.

“The studies overall have shown that there is definite improvement of learning when there’s a physical presence of adults in the room,” Dr. Yang says. “And that, of course, is very much what we would expect.”

For children younger than 18 months, researchers looked into whether including screen time along with adult supervision can impact development.

“What they found was having a background TV had a very negative effect on infants and their language development,” Dr. Yang says. “When there was background TV, parents tended to talk less. The tended to be more passive in their interactions with their children when the TV was on.”

This is especially true for the very young, even if they weren’t directly viewing the television.

“When the TV was on, it provided a very major distraction for the infants,” she says.

As children begin to develop motor skills, they can show signs of what Dr. Yang called a “video deficit effect,” wherein it took twice as long for them to learn or mimic an action if it was presented on video rather than in person. They also showed a lack of social skill development.

“When asked to reproduce that action, they weren’t able to reproduce it in real life with an adult in the room,” she says. “This is where they started to realize that perhaps these videos are categorized more as an imaginary concept rather than a real-world concept, and ultimately doesn’t become translated into their development.”

Yang said these studies show that infants should be kept away from electronic devices without adults being able to help interpret what they are seeing.

How does screen time affect language skills?

Older children – those ages 12 to 24 months – who spent two hours a day in front of a monitor show up to a six times more likelihood of language delay. And the problems compounded if they started interacting with electronic devices earlier.

“Studies show that risks for language delay were worse if they started screen time before 12 months of age,” Yang said.

Other studies showed that television had a negative impact on children who were exposed to English as a second language while they were engaging in their primary language.

But there are indications that as children begin to develop a better understanding of the world around them – at about age 17 months – spending time with educational content with an adult present can help them with vocabulary development.

“If you looked at the data in the correct way, or used a different way to interpret the data,  perhaps it actually could help with vocabulary development,” Dr. Yang says.

Not all screen time is the same. Some early research shows that touch-screen devices such as tablets can have a more positive impact development than passive devices like television. But that too requires active adult direction and high-quality educational material.

“Quality versus quantity is what matters,” Dr. Yang says.

When is screen time OK for kids?

For children ages 2 to 5 years, the picture becomes a little hazier, but generally, at this age, there are many dangers associated with screen time. Exposing children at this age to two to three hours of screen time showed increased likelihood of behavioral problems, poor vocabulary, and delayed milestones. This is especially true for children with special needs.

But there are some circumstances when it can have a positive impact. Programs and shows designed specifically to teach children can help boost school readiness, even if no adult is present.

“For things like numbers, letters, colors, shapes, spatial size and red relations, they tended to score higher on these rather than their peers who watched more general adult TV,” Dr. Yang says.

Some research also indicates that educational screen time could potentially enhance social and language skills, especially in lower-income homes. This could be because these homes previously had more limited access to learning material.

There are studies that show that boys can react differently to electronic stimulation than girls at this age. For instance, more TV at the age of 4 years led to a lower level of emotional understanding in girls. And the studies also showed that time spent on computer games led to lower emotional understanding in boys. However, Dr. Yang cautions that the matter needs to be studied further.

“Unfortunately, this is also a very subjective study, so it’s not clear exactly why or how that that truly was correlated,” she says. “But based on a couple of studies and similar findings, they felt there was enough of a correlation to at least associate those.”

How does screen time affect preteens and teens?

As children grow older, studies become more subjective. The risks of excessive screen time can continue to impact their emotional and educational development.

For them, more screen time can be associated with higher anxiety, depression symptoms, lower quality of life, lower psychological well-being, lower school functioning, lower academic achievement, lower self-esteem, poor language achievement, and poor math achievement.

But the results largely depend on what kind of media is being consumed.

“Intuitively, we know it’s probably different watching a TV show versus watching a documentary, or playing a video game that you don’t have to think versus a video game that you have to work with other children and come up with a solution together on a problem,” Dr. Yang says.

Excessive screen time is also connected to an unhealthy diet, as well as weight problems. One study found that kids who spent two or more hours looking at a screen have a 42 percent greater risk of being overweight.

The studies found some unanticipated results. One paper found that screen time use on weekends had worse outcomes than weekday screen time use. This could be become weekend usage was more likely to be for entertainment, while weekday usage favored educational fare, she said.

When can screen time help?

Screen time isn’t all bad. In fact, researchers found that extremely low screen time actually tended to correlate with worse mental health scores. And as they increased the amount of screen time, that showed a moderate improvement in their mental health – but a limit does exist.

“After a certain point, it started worsening their mental health again,” Dr. Yang says,

A study from New Zealand indicates that spending time around the color green — from walks outside to plants in the classroom — can help reverse the negative effects of screen time.

They noted that the higher the amount of “green time,” regardless of screen time, showed an increased self-efficacy, positive identity and decreased anxiety in teenagers,” Dr. Yang says.

Another important way to counter the impact of screen time is to maintain a healthy lifestyle: get enough sleep, eat right and maintain physical activity.

Dr. Yang cautions that the studies she researched were not perfect and more work needs to be done. Many show an association between screen time and developmental issues, not direct causation.

Also, data was self-reported, meaning that parents reported the amount of screen time their children experienced.

Some parents can “feel like, ‘Oh, this really affecting my child, so I’m going to report higher scores or worse scores,” Dr. Yang says.

She stressed the importance of doctors recognizing children who are at risk and discussing these issues with them and their parents.

“It is important in certain kids to take the time to talk about that screen time they’re getting and how it’s affecting them,” Dr. Yang says.

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