After years of speculation, there's now evidence to suggest that high exposure to screens in preschool-age children may be linked to lower brain development. The results are particularly notable since the human brain develops at its most rapid rate during those formative years.
A new report published in JAMA Pediatrics this week found that preschool-age children whose screen exposure exceeded the recommended amounts had more disorganized - and lower levels of - white matter in the brain. White matter is critical for fostering language, literacy and cognitive skills. Less white matter essentially means that the brain isn't running at its optimal rate.
"This is the first study to document associations between higher screen use and lower measures of brain structure and skills in preschool-aged kids," John Hutton, a pediatrician, clinical researcher at Cincinnati Children's Hospital, and lead author of the paper, told CNN. (It's not the first study to look at the effect of screen time on children's development, however).
The researchers examined the screen time habits and cognitive skills of 47 children ages 3 to 5 and conducted brain scans on each participant.
Prior to the scans, the children took a cognitive test and the parents filled out a survey based on of the American Academy of Pediatrics' (AAP) screen time recommendations.
The final score, called the ScreenQ score, was based on a number of criteria, including whether a child had a television in their room, if they were exposed to screens before 18 months, how much time they spend in front of screens, and whether they watched alone or with an adult.
Scores ranged from zero to 26.
The higher the score, the less of an adherence to general screen time recommendations from the AAP. Higher ScreenQ scores were associated with poorer expressive language and poorer cognitive skills, including the ability to quickly name objects.
The average score was 8.6 and the median amount of screen use was an hour and a half per day.
Screens themselves may not be inherently harmful, however, The New York Times reported. The issue could be that screens are replacing activities that promote brain development, including communicating with other people and reading.
While the paper's findings may help to inform parents' approach to screen time, it's important to note that the researchers only sampled a small group of children and the results only offer a snapshot in time.
The ideal type of playing, according to the AAP, promotes language, pretending, and problem solving. That's often best achieved without digital screens.
For young children, one of the main issues is transitioning from what they experience on a two-dimensional screen to that what they see in the real, three-dimensional world.
"If you give a child an app where they play with virtual Legos, virtual blocks, and stack them, and then put real blocks in front of them, they start all over," Dimitri Christakis, a pediatrician at Seattle Children's Hospital and co-author of the AAP screen times guidelines, said in an interview with 60 Minutes last year.
Since screens are essentially inescapable at this point, the AAP released comprehensive guidelines for families.
According to the AAP, a cell phone shouldn't be used to calm down an aggravated child, because that could preclude them from developing crucial emotional coping skills. When a child is given an iPad to use, another adult should also participate in the video game or app, to encourage social interactions.
Jordan Shapiro, a research psychologist and author of "The New Childhood," echoes the AAP's recommendations. He urges parents to focus more on how children are using devices. For example, Shapiro also advises parents to sit and talk to their children while they're watching a video or playing a video game.
"[Screens] are a part of our lives so it becomes about teaching kids how to live with them in a healthy and ethical way," Shapiro told Insider in January.
In April, the World Health Organization also issued its first guidance for screen time in children: Children younger than 18 months shouldn't be exposed to any screens outside of video chatting. Children 5 and younger should get no more than an hour of screen time a day.
That the tech world's most famous figures - the ones who made millions off of screens - limited their children's exposure, should have served as an early admonishment to parents.
Bill Gates, the former CEO of Microsoft, didn't give children cell phones until they were 14. Back in 2007, Gates also set a cap on the amount of time his daughter could spend in front of a screen when he felt she was developing an unhealthy attachment to a video game.
In 2010, Steve Jobs, who served as Apple's CEO until his death, told a New York Times reporter that his children had never even used an iPad.
Still, the medical world is just beginning to understand the implications of the use of screens in children. The authors of the new JAMA report noted that more research needs to be done to better understand how and why screens can interfere with brain development.
To get to that point, the National Institutes of Health has embarked on a decade-long study to investigate how screens affect children over an extended period of time. The NIH study will follow more than 11,000 children, and monitor how the use of digital screens like smartphones, video games could change a young and developing brain.
It's going to be a while before we get those answers. Until then, parents will have to continue to set their own limits and monitor how exposure to screens affects their children's growth and development.
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