China News Service, Shanghai, June 7th (Chen Jing Jiang Rong) With the introduction of various electronic devices into thousands of households, it has become a very common phenomenon for children to come into contact with electronic screens.

Excessive screen exposure is the same globally.

A team from the National Children's Medical Center (Shanghai) and the Shanghai Children's Medical Center affiliated to Shanghai Jiaotong University School of Medicine found that excessive screen exposure during the age of 0-3 can affect children's cognitive control ability, which in turn affects the level of total IQ and attention. development and lead to an increase in hyperactive behavior.

  Studies have shown that children with significantly increased screen exposure after the age of 3 are mainly affected by their intelligence level: lower language comprehension 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 long been engaged in a series of studies on the impact of lifestyle on children's health, and has established a lifestyle and healthy development cohort (SCHEDULE cohort) covering more than 220,000 children in 10 provinces and cities.

The data of this study come from the SCHEDULE birth cohort, which was established in 2012. Participants entered the study from the third trimester of the mother's pregnancy and have been followed up until the child is 10 years old.

Through the data tracking of these children, the influence of different trajectories of screen exposure on cognitive development in early life of infants and young children was clarified.

  The researchers found through the SCHEDULE preschool cohort data that 76% of children in Shanghai had started to touch the screen before the age of 2, and 24% of the children began to passively watch TV with their parents before the age of 1. At the same time, many parents also Use the mobile phone as a tool to coax children, and use the cartoons and games in the mobile phone to attract and seduce the children.

  The study found that in addition to the younger age of screen exposure, the length of screen exposure is also worrying. Taking 3-year-old children who have just entered kindergarten as an example, their daily average screen time has reached 2 hours and 50 minutes, and 78.6% of Children's screen time exceeds the guideline recommendation of 1 hour per day.

  What are the effects of excessive and premature screen exposure on early childhood development?

In fact, people's understanding of this problem was not very clear before, making it difficult to perfect prevention and control strategies.

It is reported that the research of Jiang Fan's team started from the third trimester of the mother's pregnancy, and carried out a continuous follow-up study on infants and young children for more than 6 years.

  The researchers assessed children's average daily screen time and screen exposure at 9 months, 12 months, 18 months, 24 months, 36 months, 48 ​​months, and 72 months, starting at 6 months after birth. At the same time, during the process of children's growth, the research team regularly evaluates children's cognitive development, language and psycho-behavioral problems.

  The results of the study found that there were three main trajectories of screen exposure of children under 6 years old with age: one group of children under the age of 6 had "persistently low" screen exposure, another group of children showed "early growth" characteristics; It is characterized by "late growth".

A comparative study of the developmental levels of these three groups of children found that at baseline (just after birth), the three groups of children had significant differences in cognitive function (measured by the Wechsler Intelligence Scale) and psychobehavioral problems at the age of 6 years.

In terms of psychological behavior, compared with the "continuously low group" of screen exposure, the incidence of psychological problems in the "early growth group" was significantly increased, especially the impairment of hyperactivity and inattention.

  Jiang Fan told reporters that children under the age of 6 who are exposed to screens for less than 1 hour a day have the best cognitive and psychological development levels.

If more screen exposure occurs early in infancy and early childhood, even if screen exposure declines later, it can still have significant adverse effects on children.

The expert explained that this is because infants and young children, especially within the age of three, are the most rapidly developing stages of the brain. During this period, under the stimulation of the rich environment in the real world, the positive cognitive processing of children will make the pre-cerebral cortex and the brain. The functions of various brain regions are rapidly connected to form the networks required for cognitive control.

However, for electronic products such as TV, the strategy adopted by the children's brain is passive processing. Long-term exposure to such screen stimuli will cause the cognitive control network to fail to develop fully.

  Studies have found that even highly downloaded educational software is filled with a lot of distracting ads and animations, and very few that simulate human 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 the impact of excessive and premature exposure of screens on children's brain development.

Combined with the existing screen exposure guidelines, the evidence provided by this study suggests that parents should try to avoid exposure to electronic screens for children before the age of 2, especially before the age of 18 months, and the screen exposure time of children after the age of 2 should also be limited to 1 hour per day. within.