Spending hours glued to a smartphone can trigger a chemical imbalance in teenagers’ brains and make them depressed, scientists have found.
Brain scans of youngsters addicted to their phones showed heightened levels of chemicals that slow down brain signals.
These teenagers were then more likely to be depressed, anxious and sleepy.
Health experts are increasingly worried about soaring use of smartphones among British teenagers. Three quarters of 11 to 15-year-olds spend at least two hours a day using a handheld device, up by 50 per cent compared to 15 years ago.
The scientists behind the latest study, from Korea University in Seoul, said: ‘More and more people are becoming increasingly dependent on smartphones and other portable electronic devices for news, information, games, and even the occasional phone call.
‘Along with a growing concern that young people, in particular, may be spending too much time staring into their phones instead of interacting with others, come questions as to the immediate effects on the brain and the possible long-term consequences of such habits.’ The team carried out brain scans on 38 youngsters with an average age of 15, half of whom had been diagnosed with smartphone or internet addiction.
Addiction was diagnosed by assigning a score based on how much time they spent on their phones and how this affected their daily routine, social life, productivity and sleep.
The scans showed that the addicted teenagers had higher levels of gamma-Aminobutyric acid, or GABA, a chemical that slows down brain signals, in the anterior cingulate cortex – the part of the brain that controls emotion, particularly anxiety, as well as functions such as vision and motor control.
And they had lower levels of glutamate-glutamine, or Glx, which causes nerve cells to be more electrically excited.
The findings, which the team presented yesterday at the Radiological Society of North America, suggest the brain may dampen down messaging between brain cells as it is bombarded by information from electronic gadgets.
Study leader Professor Hyung Suk Seo said the ratio of GABA to Glx directly correlated with the teenagers’ addiction score – meaning the more they used their smartphones, the worse the imbalance.
There was also a direct link to increased levels of depression and anxiety.
Twelve of the addicted teenagers underwent nine weeks of counselling to reduce their gadget use, after which the imbalance was either reduced or completely eradicated.
Professor Seo said the findings ‘may contribute to our understanding of the pathophysiology of and treatment for addictions.’
A World Health Organisation report in May put the UK towards the top of a league table of gadget use in 42 European countries. For girls, Scotland ranked the highest, with Wales coming fourth and England second. For boys, Wales was second in the list, Scotland third and England 15th.
An Ofcom report published last year suggested the average British three and four-year-olds now use iPads and smartphones for one hour and 11 minutes a day, while those aged five to 15 spend two hours and eight minutes.
© Daily Mail