Following the publication of a relevant paper in the authoritative medical journalJAMA Pediatrics last year, the team led by Professor JIANG Fan from the National Children’s Medical Center (Shanghai) and Shanghai Children’s Medical Center affiliated to Shanghai Jiao Tong University School of Medicine, and Associate Researcher ZHANG Yunting from the Child Health Advocacy Institute, recently published their latest research findings on the impact of screen exposure on early mental health of children in the same journal. Through a large population-based cohort study, the team found that whatever on-screen content preschool children watch, they may suffer from significantly increasing mental health risks as long as their screen exposure exceeds 1 hour per day, and the longer their screen exposure is, the higher the risks would be. With a given screen exposure, children may suffer from higher mental health risks when watching entertainment or non-children programs, compared to educational ones. This is the conclusion of a 3-year observation of 15,965 preschool children.
As information technologies penetrate our daily lives, it has become a new normal that children are increasingly exposed to television and electronic products at lower ages. Screen exposure refers to a series of activities in which children are exposed to television and electronic products, such as watching TV, playing video games, surfing the internet, and using smartphones. According to the World Health Organization, children under the age of 2 should avoid exposure to screens, and those aged 2-5 should have an average screen time of no more than 1 hour per day. However, preliminary research by the team found that 24% of children start to be exposed to screens before the age of 1, with 76% before 2, and out of 3-year-old children who have just entered kindergarten, up to 78.6% have an average daily screen time exceeding the WHO limit. Excessive screen exposure is common not only in China, but around the globe. 85% of Canadian children of the same age exceed the screen time limit, and in Australia, the figure is 74%. Apparently, screen exposure has become a global problem that arouses increasing concern.
Professor JIANG Fan’s team has been engaged in a series of studies on the impact of lifestyle on children’s health for long, and established a cohort of over 220,000 children for studies on their lifestyle, health and development (SCHEDULE cohort). In fact, the team has conducted follow-up visits to the SCHEDULE-B cohort for over 6 years, to find that excessive screen exposure resulted in a significant adverse effect on children’s cognition, psychology and behaviors even if it decreased later on.
After the paper was published, many educators and parents started to recognize the impact of excessive screen exposure, but they raised another question - could children avoid the impact by watching educational programs? Worldwide, we didn’t see much research on how different on-screen contents affected children, and there wasn’t scientific evidence based on which we could answer the question. So the team tracked and recorded the data of 15,965 kindergarten children for three years, using the SCHEDULE-P cohort as supported by the Shanghai Municipal Education Commission, and eventually found the answer. Findings indicate that for preschool children, screen exposure exceeding 1 hour is a risk factor for mental and behavioral problems. With a given screen exposure, educational video programs have a less negative impact on children’s mental health than other on-screen contents, while non-children video programs have the greatest negative impact. The team also revealed for the first time the characteristics of on-screen content that children aged 3-6 are exposed to - educational and entertainment video programs account for a lion’s share among younger children, and as they grow with skills and needs to socialize, they increasingly use social media. These findings provide a strong scientific basis on which parents could bring up their children.
This project was strongly supported by the Shanghai Municipal Education Commission, and Professor YU Zhangsheng from the Clinical Research Center of Shanghai Jiao Tong University School of Medicine also provided great support and guidance for data analysis and statistics of the paper. Its first author is WANG Haiwa, a PhD student in pediatrics at Shanghai Jiao Tong University School of Medicine, andtheco-first author is Dr. ZHAO Jin from the Department of Developmental & Behavioral Pediatrics at Shanghai Children’s Medical Center.
Currently, the team is further exploring the impact and related mechanism of early excessive screen exposure on children’s brain structure and its functional development through magnetic resonance imaging based on the SCHEDULE-B cohort. At the same time, they focus on the core elements of screen exposure that affect children’s cognitive development, and on this basis, they expect to figure out some intervention that could help reduce the impact.
