As technological innovations such as mobile phones and video games have become more widespread in recent decades, young people are spending more and more time on these devices. And too much screen time can be detrimental to the developing young minds and bodies.
While various agencies offer guidelines on how much time children should spend on screens each day, Dr. Michelle Yang, a CHOC resident, wanted to know why these recommendations exist and how helpful they really are. She discussed her research at a recent Grand Rounds talk at CHOC titled “Impact of Screen Time on Children and Adolescents.”
While the effects of unrestricted access are negative, there are circumstances in which screen time can help a child learn certain skills. And a little time in front of a device can actually help improve a child’s mental health.
How has screen time use changed among young people?
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 in front of screens, two hours more than in 2015.
Teens (ages 8 to 12) spend about 5 ½ hours a day on devices, an hour more than a decade ago. That means some young people spend half of their waking day in front of a screen. Usage skyrocketed in 2019, just before the COVID-19 pandemic began to spread.
At least half of those hours are spent watching TV, not just on a phone or tablet, says Dr. Yang, but the studies looked at different types of media.
“I think it’s really important to understand why we make the recommendations we make and what the rationale is,” says Dr. Yang.
What screen time is recommended for children and teenagers?
So what are the recommendations? According to the American Academy of Pediatrics (AAP) and the US Centers for Disease Control (CDC), they are:
- Younger than 18 months: No screen time, except for video chats with family and friends
- 18 to 24 months: Only high-quality educational media with parental involvement
- Age 2 to 5 years: No more than one hour per day
- From 5 years: No more than two hours per day, during which you talk to a parent or family member about what you have seen
- Pre-adolescence and teens: Different impacts on mental health, academic success and social skills; it is important to balance screen time with physical activity and healthy habits.
Instead of having children spend all day in front of screens, the agencies suggest some simple, age-appropriate alternatives: playing a ball game, riding a bike, working in the garden, dancing to music or walking the dog.
Learn how to limit teen screen time.
What role does the presence of an adult play during screen time?
Dr. Yang noted that limiting screen time is only part of the solution. It is also important for adults to be actively involved, especially with younger children.
“Overall, the studies have shown that learning improves significantly when adults are physically present in the room,” says Dr. Yang. “And of course, that’s exactly what we expected.”
In children under 18 months, researchers examined whether screen time and adult supervision can affect development.
“They found that having a TV on in the background had a very negative effect on young children and their language development,” says Dr. Yang. “When there was a TV on in the background, parents spoke less. They were more passive in their interactions with their children when the TV was on.”
This is especially true for very young children, even if they are not watching television directly.
“When the television was on, it was a huge distraction for the young children,” she says.
As children begin to develop motor skills, they may show signs of what Dr. Yang calls a “video deficit effect,” where it takes twice as long for them to learn or imitate an action when it is presented on video rather than in person. They also showed a lack of social skill development.
“When they were asked to reproduce this action, they were unable to reproduce it in real life with an adult in the room,” she says. “This is where they realized that perhaps these videos are categorized as an imaginary concept rather than a real concept and ultimately this does not impact their development.”
Yang said these studies show that young children should be kept away from electronic devices without adults to help them interpret what they see.
Learn more about the effects of screen time on vision.
What impact does screen time have on language skills?
Older children – aged 12 to 24 months – who spend two hours a day in front of a
Monitors show up to six times higher likelihood of speech delay. And the problems are exacerbated when children begin interacting with electronic devices at an earlier age.
“Studies show that the risk of language delay is greater when children start using screens before 12 months of age,” Yang said.
Other studies showed that television had a negative impact on children learning English as a second language in addition to their native language.
However, there is evidence that children who begin to develop a better understanding of the world around them at around 17 months of age can be helped to build their vocabulary by engaging with learning content in the presence of an adult.
“If you look at the data in the right way or interpret it differently, it may actually help develop your vocabulary,” says Dr. Yang.
Not all screen time is created equal. Some early research shows that touchscreen devices such as tablets can have a more positive impact on development than passive devices such as televisions. But even these require active adult guidance and high-quality teaching materials.
“It’s about quality rather than quantity,” says Dr. Yang.
When is screen time okay for children?
For children ages 2 to 5, the picture becomes a little more blurred, but in general, there are many dangers associated with screen time at this age. If children are exposed to two to three hours of screen time at this age, they are more likely to experience behavioral problems, poor vocabulary, and delayed development. This is especially true for children with special needs.
However, there are some circumstances in which it can have a positive impact. Programs and shows specifically designed to impart knowledge can increase children’s school readiness, even when no adult is present.
“They tended to perform better on things like numbers, letters, colors, shapes, spatial sizes and red relationships than their peers who watched more general adult television,” says Dr. Yang.
Some research also suggests that time spent in front of screens can improve social and language skills, especially in lower-income families. This may be because these families previously had more limited access to learning materials.
There are studies that show that boys at this age may respond differently to electronic stimulation than girls. For example, watching more television at age 4 led to lower emotional understanding in girls. And the studies also showed that time spent playing computer games led to lower emotional understanding in boys. However, Dr. Yang cautions that the matter needs further study.
“Unfortunately, this is also a very subjective study, so it’s not clear why or how exactly this correlation existed,” she says. “But based on some studies and similar results, they felt the correlation was enough to at least link them together.”
DEVELOPMENT
Age groups and development stages
What impact does screen time have on adolescents and teenagers?
As children get older, learning content becomes more subjective. The risks of excessive screen time can continue to impact their emotional and academic development.
For them, more screen time may be associated with greater anxiety, symptoms of depression, lower quality of life, lower psychological well-being, poorer school performance, poorer academic achievement, lower self-esteem, poorer language skills, and poorer math performance.
However, the results depend heavily on what type of media is consumed.
“Intuitively, we know that there is probably a difference between watching a television show or a documentary, or playing a video game where you don’t have to think, or a video game where you have to work with other children to find a solution to a problem together,” says Dr. Yang.
Excessive screen time is also linked to unhealthy eating as well as weight problems. One study found that children who spend two or more hours in front of a screen have a 42 percent higher risk of becoming overweight.
The studies found some unexpected results. One study concluded that weekend screen use produced worse outcomes than weekday use. This may be because weekend use was more likely to be for entertainment, while weekday use was more likely to be for educational purposes, she said.
When can screen time help?
Screen time isn’t necessarily bad. In fact, researchers found that extremely low screen time was even correlated with worse mental health scores. And when they increased screen time, they showed a moderate improvement in their mental health—but there’s a limit.
“At a certain point, her mental health began to deteriorate again,” says Dr. Yang.
A study from New Zealand shows that spending time with the color green – from walking outside to plants in the classroom – can help reverse the negative effects of screen time.
They found that higher levels of ‘green time’, independent of screen time, led to higher self-efficacy, positive identity and lower anxiety in teens,” says Dr. Yang.
Another important way to counteract the effects of screen time is to maintain a healthy lifestyle: getting enough sleep, eating right and staying physically active.
Dr. Yang points out that the studies she reviewed were not perfect and more work is needed. Many show a link between screen time and developmental problems, but not a direct causal link.
In addition, the data was self-reported, meaning that parents reported how much time their children spent in front of the screen.
Some parents may feel, “Oh, this is really affecting my child, so I’m going to report higher or lower scores,” says Dr. Yang.
She stressed the importance of doctors identifying children at risk and discussing these issues with them and their parents.
“For some children, it’s important to take the time to talk about the time they spend in front of the screen and the impact it has on them,” says Dr. Yang.
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