"When all those developments occurred, people still ate together, they shopped face-to-face, played games, they certainly dated and they worked face-to-face," she said. "Now you can do all those activities without meeting another human being. Surely that has an impact on the kind of human being you become." Loading Replay Replay video Play video Play video When Baroness Greenfield raised these concerns in 2009 she said she was attacked by medical experts and in the mainstream media with headlines such as "Baroness says computers rot the brain". "Sadly those headlines have been increasingly vindicated," said Baroness Greenfield, who will meet with the Victorian Department of Education to discuss the use of iPads and other screens in schools.

The extent to which screen time affects psychological and neurological health remains controversial. A Oxford University study released last month concluded screen time had little effect on the psychological wellbeing of teenagers. "We found little clear-cut evidence that screen time decreases adolescent wellbeing, even if the use of digital technology occurs directly before bedtime," said Professor Andrew Przybylski, director of research at the Oxford Internet Institute and co-author on the study. Loading The World Health Organisation guidelines released last week recommended no passive screen time for children under the age of one and no more than one hour a day for those under five in order to limit the negative effects of a sedentary lifestyle on developing brains and bodies. Previous studies have suggested a link between excessive screen time, shorter attention spans, addictive personalities, recklessness, low empathy, poor interpersonal skills and a weakened sense of identity.

A 2011 study found children who spent hours playing video games had brains like gamblers. MRI scans showed they both had enlarged areas of the brain that releases dopamine; critical to arousal and our risk-reward response Dopamine also inhibits the prefrontal cortex, which is associated with decision making, planning and moderating behaviour. Loading "We know when you play with a screen it is an intensely stimulating experience," Baroness Greenfield said. "The lights are brighter, the sounds are greater, the action is faster and the feedback is more immediate." A 2014 US study found students were not comfortable spending as little as six to 15 minutes in a room by themselves with nothing to do but think, with many preferring to give themselves electric shocks instead of being along with their thoughts.

Loading "Does this mean we are going to live in a world where we are much more dependent on external stimulation, [where people] need excitement all the time?" Baroness Greenfield said. "It’s quite a scary thought. I don’t think we are going to be like computers but more like volatile three-year-olds." She warned younger generations may be "heading towards an existence where there is no inner narrative, no inner train of thought". She advocated minimising screen time and more time on activities that have a sequence of events to rewire our brains.