When people ask me what frightens me most about kids using smartphones, I always say the cognitive effects.
Brain drain: Professor Mark Williams is concerned about the known link between overuse of devices and a decline in cognitive ability.
We know there are links between young people overusing devices and a decline in cognitive abilities, as well as problems with attention, focus and memory.
Some of my colleagues at Macquarie University recently published a review and meta-analysis of 34 studies looking at neuropsychological deficits in children and teenagers who had screen-use disorders – basically what can be classified as screen addictions.
Their findings showed strong evidence of impacts on attention, focus and executive functioning in these young people, but also changes in their brains that were visible on scans, with the loss of grey and white matter in areas of the frontal lobe that are associated with learning and memory.
Yes, you read that correctly.
Overuse can result in young people losing brain capacity.
These studies relate to the roughly three per cent of teenagers who are classified as having a clinical screen overuse disorder, but the latest figures show the average Australian teenager is spending four to six hours a day on social media, and a total of up to eight hours a day using screens for leisure.
For the past 10 years, we have been putting these devices into our children's hands from an early age. It's an incredible experiement we're putting them through, and we don't know what the outcome will be.
Recent research from the University of North Carolina shows brain changes related to habitual checking of social media in Grade 6 and 7 students over three years. A third of the children – those who were frequently checking their feeds – showed significant changes in brain areas involved in emotion, motivation and cognition.
Brains are very much a use-it-or-lose-it organ: if you challenge yourself through thinking, problem-solving and learning, you develop new connections in your brain. If you don't challenge yourself, not only do new connections not form, but the old ones start to die off.
Recently released Australian Bureau of Statistics (ABS) figures show dementia is on track to overtake heart disease as Australia's leading cause of death, possibly within the next few years.
Early-onset dementia on the rise
Dementia might be thought of as an old person's disease, but younger people can also be affected. Early onset dementia usually affects adults aged between 30 and 65, but there are rare cases of people being diagnosed in their twenties. In the past, the majority of cases of younger-onset dementia were believed to be inherited.
The latest figures from the Australian Institute of Health and Welfare indicate there are about 29,000 Australians under the age of 65 now living with younger-onset dementia, and they expect this to increase to 41,000 by 2054.
However, the numbers from the United States are far more disturbing, with a 2020 report showing that between 2013 and 2017, younger-onset dementia in 30-44-year-olds had spiked by 373 per cent.
All age groups recorded an increase, with a 311 per cent rise in the 45-54 age group, and a 143 per cent rise for 55-64s, but it was the Millennials and Gen Xers who were the hardest hit.
Some people cite the improvement in diagnostic techniques as being behind this change, but if that were the case, we would be seeing a similar increase across all ages. We aren't.
The report did not speculate on the cause for this dramatic increase in younger-onset dementia. Still, there is nothing else that has happened in the past 10 years that can explain this change apart from the global rise to dominance of the smartphone from about 2012.
We know that people with lower cognitive capacity are more susceptible to dementia.
We know overusing smartphones can result in lower cognitive capacity.
We may argue that correlation is not causation, but the correlation between lead in water and problems with children's brain development seen across the world from the mid-20th century was enough for governments to spend the equivalent of millions of dollars to replace all our water pipes.
Younger-onset dementia rates have risen at the same time as smartphones have taken over every part of our lives, and dismissing this as a coincidence will not address the problem.
Needs to know more: Professor Mark Williams says in-depth research projects are required to discover the effects of over screen use and its impact on our brains.
Screen use may or may not be the original cause of the problem, but the fact that excessive and ongoing screen use leads to changes in the brain means there is a relationship that warrants urgent further investigation.
Steps like the Federal Government's proposed social media age limit, phone bans in schools, and proposals to legislate to force social media companies to take responsibility for the harms caused by their platforms are all a step in the right direction, but we need more. We need funding for in-depth longitudinal studies.
For the past 10 years, we have been putting these devices into our children's hands from an early age. We have been allowing them to use screens at the expense of learning social skills through face-to-face interaction, working on problem solving, developing motor and language skills, and just playing outside.
It's an incredible experiment we're putting them through, and we don't know what the outcome will be.
Professor Mark Williams is an Honorary Professor in the School of Psychological Sciences at Macquarie University. He is the author of The Connected Species: How the Evolution of the Human Brain Can Save the World.
