Watching too much TV really does rot your brain

MOTHERS have been telling their children for decades that watching too much television will rot their brains.

Now it seems that they may have been right all along.

Scientists have discovered that the time spent watching TV as a teenager is linked to weak brainpower in middle age.

Experts at the University of California tracked more than 3,000 adults for 25 years. The participants, each aged 18 to 30 at the start of the project, had their physical activity and television viewing habits recorded during repeated visits.

At the end of the study, they were assessed in a series of tests to measure their thinking skills. The researchers, whose results were published in the journal JAMA Psychiatry, found that there was a strong link between the number of hours spent in front of the television and poor brain power.

And the impact seemed to be even greater among those who watched lots of TV and also carried out little exercise.

They discovered that participants who watched more than three hours of TV a

‘Low levels of physical activity’

day, and were physically inactive, were twice as likely to fall into the ‘poor’ bracket of cognitive performance.

The volunteers were tested on several aspects of mental performance. These included processing speed, or how fast the brain works, executive function, and language skills.

The scientists warned that the findings are of deep concern – particularly as so many youngsters today spend hours each day staring at a computer or TV screen, and doing little exercise.

The team, led by Tina Hoang of the Northern California Institute for Research and Education, wrote: ‘We found that low levels of physical activity and high levels of television viewing during young to mid-adulthood were associated with worse cognitive performance ... In particular, these behaviours were associated with slower processing speed and worse executive function but not with verbal memory.’

The study did not look at the causes of the link between excess television and weak brainpower. But previous studies have found being sedentary increases blood pressure and blood sugar levels, both of which may play a role.

However, Dr Andrew Przybylski, of Oxford University, said the research fell down on the fact that participants’ cognitive power was not tested at the beginning of the study – only at the end.