Children who spend seven hours on smartphones may have lower IQs, declining memory, cognitive function

Children who use screens for seven hours or more a day are showing signs that their brain cortex is thinning prematurely.The findings show that children are at risk of deteriorating memory function, perception skills and cognitive abilities, according to new major United States (U.S.) study.

The ongoing $300 million (£236mn) research is funded by the National Institute of Health and shows results of the effects of technology on children. Researchers made the early findings by scanning the brains of 4,500 children.

Scientists are in the process of following more than 11,000 nine to ten-year-olds over the course of a decade.The aim of the study, called Adolescent Brain Cognitive Development, is also to show how screen time affects emotional development and mental health.

The researchers also determined that children who spend more than two hours of daily screen time score lower on thinking and language tests. The brain cortex is the outermost layer of neural tissue that processes information from the physical world. It is critical for cognitive functions such as perception, language, memory and consciousness but thins as we mature into old age.

Though the difference was significant from participants who spent less time using smart devices, the study director cautioned against drawing a conclusion. The scientists won’t be able to draw a definitive outcome until they follow them over the course of several years. A 2014 study showed that there is a direct correlation between the thickness of the brain cortex and IQ score.

The cortex begins to thin after the age of five or six as part of the normal aging process.The findings showed that people with a significant increase in IQ did not have the expected cortical thinning and people with a significant decrease in IQ had exaggerated cortical thinning.A major data release of the initial data is scheduled for early 2019.