With various electronic devices entering thousands of households, children's contact with electronic screens has become a very common phenomenon. Too much screen exposure is also true worldwide. The research team of Professor Jiangfan from the National Children's Medical Center (Shanghai) and Shanghai Children's Medical Center affiliated to the medical school of Shanghai Jiao Tong University found that excessive screen exposure during the age of 0-3 years would affect children's cognitive control ability, thus affecting their overall IQ level and attention development, and leading to increased hyperactivity.
The research shows that the intelligence level of children with significantly increased screen exposure after the age of 3 is mainly affected by lower language understanding ability and perceptual reasoning ability. It is reported that the research results of Professor Jiang Fan's team on the impact of screen exposure on early childhood development were published online in the international authoritative journal JAMA pediatrics.
Professor Jiang Fan's team has been engaged in a series of studies on the impact of lifestyle on children's health for a long time, and has established a lifestyle and health development research cohort (schedule cohort) covering more than 220000 children in 10 provinces and cities. The data of this study comes from the schedule birth cohort, which was established in 2012. The participants entered the study from the third trimester of pregnancy and have been followed up to the age of 10. Through the data tracking of these children, the effects of different trajectories of screen exposure on cognitive development in early life of infants were clarified.
Through the study of the schedule preschool cohort data, the researchers found that 76% of the children in Shanghai began to touch the screen before the age of 2, while 24% of the children began to watch TV passively with their parents before the age of 1. At the same time, many parents also use mobile phones as a tool to coax their children, using cartoons and games in mobile phones to attract and tease their children.
The study found that in addition to the younger and younger age of touching the screen, the length of screen exposure is also worrying. Taking the 3-year-old children who have just entered the kindergarten as an example, the average screen time per day has reached 2 hours and 50 minutes, and 78.6% of the children's screen time has exceeded the recommended standard of 1 hour per day.
What impact will too much and too early screen contact have on early childhood development? In fact, previously, people's understanding of this problem was not very clear, making it difficult to improve the prevention and control strategy. It is reported that the research of Jiangfan team started from the third trimester of pregnancy and carried out continuous follow-up research on infants for more than 6 years.
From 6 months after birth, the researchers assessed the average daily screen use time and the main contents and methods of screen exposure of children at the ages of 9 months, 12 months, 18 months, 24 months, 36 months, 48 months and 72 months respectively; Meanwhile, in the process of children's growth, the research team regularly evaluates children's cognitive development, language and psychological behavior problems.
The results show that the screen exposure of children under 6 years old has three characteristics with age: one group of children has "sustained low" screen exposure, and the other group has "early growth" characteristics; Another group is characterized by "late growth". A comparative study on the development level of the three groups of children found that at the baseline (just after birth), there were significant differences in cognitive function (measured by Wechsler Intelligence Scale) and psychological and behavioral problems among the three groups at the age of 6. In terms of psychological behavior, the incidence of psychological problems in the "early growth group" was significantly higher than that in the "sustained low" group of screen exposure, especially in hyperactivity and attention deficit.
Jiang Fan told the reporter that the cognitive and psychological development level of children under the age of 6 whose daily screen exposure is always controlled within 1 hour is relatively the best. If more screen exposure occurs in the early childhood, even if the screen exposure decreases later, it can still have a significant adverse effect on children. The expert explained that this is because infants and young children, especially those under the age of three, are at the fastest stage of brain development. During this period, under the rich environmental stimulation of the real world, children's positive cognitive processing will quickly connect the functions of the anterior cerebral cortex and various brain regions, thus forming the network required for cognitive control. However, for electronic products such as TV, the strategy adopted by children's brain is passive processing. Long-term exposure to such screen stimulation will lead to the insufficient development of cognitive control network.
Some studies have found that even educational software with a high number of downloads is full of a large number of distracting advertisements and animation, but few can simulate interpersonal social interaction and provide good cognitive stimulation.
Jiang Fan pointed out that we should not only make good use of new technologies to help children's development and education, but also prevent excessive and premature exposure of the screen from affecting children's brain and intellectual development. Combined with the existing screen exposure guidelines, the evidence provided in this study suggests that parents should try to avoid letting children before the age of 2, especially before the age of 18 months, touch the electronic screen, and the screen exposure time of children after the age of 2 should also be controlled within 1 hour a day.