Baroness Greenfield, a top neuroscientist, said children need to turn off their PCs and spend time outside getting fresh air instead.
Research suggests youngsters can spend an astounding 2,000 hours a year in front of their computer screens, running the risk of addiction.
Baroness Greenfield said: 'Screen technologies cause high arousal which in turn activates the brain system's underlying addiction. This results in the attraction of yet more screen-based activity.'
She went on to say that the brain can be 'temporarily disabled by activities with a strong sensory content - 'blowing the min', adding that 'they can be inactivated permanently by degeneration - ie. dementia'.
She underlined the need for children to have time away from their gadgets and enjoying the freedom of the outdoors, saying:
'There is a need to be outside, to climb trees and feel the grass under your feet and the sun on your face.'
Do you agree?
Do you think your kids spend too much time online? Or is this just another guilt study for parents?
More:Advice And Health
Suggested For You
Get top stories and blog posts emailed to me each day. Newsletters may offer personalized content or advertisements. Learn more