Children who spend more than two hours per day looking at an electronic screen demonstrate decreased memory, diminished language skills, and shortened attention spans. This was the conclusion of some recent landmark research published by Lancet Child and Adolescent Health. The observational study involved 4,520 children between the ages of eight and eleven years. Parents were asked to track three things about their children and then the children were asked to complete a variety of cognitive (brain) tasks.
The three things the parents tracked were:
- the amount of time their child spent each day looking at a screen (smart phone, tablet, television, or computer)
- the number of minutes per day their child spent in physical activity
- the number of hours of sleep their child had
The study revealed when a child spent more than two hours a day looking at a screen, he or she demonstrated a decrease in working memory and executive processing speeds, decreased attention spans, and lowered language and executive function skills. Working memory is the type of memory we use to recall information we store for a short amount of time, such as instructions given to complete a task or a shopping list. Executive functioning includes things such as, paying attention, organizing and planning, initiating tasks and remaining focused on them, regulating emotions, and self-monitoring.
The findings published by Lancet bolstered the current recommendations on media usage established by the American Academy of Pediatrics (AAP). The AAP’s recommendations include:
- Avoiding digital media (other than video chatting) for children younger than 18 to 24 months of age
- Limiting screen time for children 2 to 5 years of age to one hour a day of high-quality programming, such as Sesame Street
- All learning apps are not the same. Do your research on learning apps by using organizations such as www.commonsensemedia.org
While the study provided important information, it did not come to a definitive conclusion on why more than two hours of screen time diminished cognitive (brain) function. But, the researchers offered some possible reasons and encouraged more research in these areas. The possible reasons given were:
- The effect of blue light on the brain
- Too much screen time interfering with adequate sleep
- Hours spent looking at a screen limits physical activity
- Excessive screen time replaces time spent on more cognitively challenging activities
Blue light is the common waveform of light present in electronic screens. It has been demonstrated in Harvard research to interfere with the body’s production of melatonin. Melatonin is the chemical which promotes sleep. Exposure to blue light during the evenings has also been shown to increase a person’s risk for obesity and diabetes. To improve sleep, the Harvard researchers recommended avoiding looking at electronic screens two to three hours before bedtime.
While the Lancet research is important, it raises many concerns and questions for parents. A few minutes on the smart phone while in the checkout line and a TV show or two before bed can quickly add up to a total of two hours/day. We know screens are a part of our lives, whether at home, school, or in the workplace. But, this research demonstrates, electronics don’t come without risks. There is now clear evidence too much screen time is harmful to the developing brain of a child.
Media Tips from the American Academy of Pediatrics
Apps to help you limit screen time