Just when experts thought that children could not swallow another mouthful of media time, the kids went on to devour almost another meal of it, a new Kaiser Family Foundation study reveals.

Kaiser’s 2005 study showed that young Americans between the ages of 8 and 18 spent a bit less than six and a half hours a day using electronic devices such as a smart phone, computer or television. By 2009 that figure had grown to more than seven and a half, or more than 52 hours a week -- and that’s without counting the hour and a half they spend texting, or the half-hour they talk on their cellphones. And without Twitter…

“This is a stunner,” said Donald F. Roberts, a Stanford communications professor emeritus who is one of the authors of the study. “In the second report, I remember writing a paragraph saying we’ve hit a ceiling on media use, since there just aren’t enough hours in the day to increase the time children spend on media. But now it’s up an hour.”

In fact it’s worse than that. By multi-tasking (talking on the phone while watching a video, surfing the internet while listening to music…) kids are packing nearly 11 hours of media content into seven and a half hours. The trend is encouraged by parents who allow television sets and computers with internet connections in bedrooms, and who don’t have rules like: no television during meals and no cellphone/iPod use in bed at night. Rules do make a difference.

The big winners in this trend are obviously the mobile phone companies and the commercial world they bring to the fingertips (forget about “research”). But what is the effect on kids of spending almost every waking minute, apart from time in school, connected?

The heaviest users -- those consuming at least 16 hours a day -- were more likely to have poor grades and to report that they were bored or sad, or that they got into trouble, did not get along with their parents and were not happy in school. Of course, it is possible that these problems are driving the excessive media use, rather than the other way around.

But even what is now normal use, according to this research, must interfere seriously with family life, real friendship, study and reflection -- amongst other things. And it can only entrench habits of consumerism and the desire for instant gratification.

In another article on this theme one expert suggests that the “I want it now” effect will be greatest for the youngest children now starting out with their touch screens and robot pets:

“They’ll want their teachers and professors to respond to them immediately, and they will expect instantaneous access to everyone, because after all, that is the experience they have growing up,” he said. “They should be just like their older brothers and sisters, but they are not.”

A British study announces that texting actually helps children to spell. Well, great. But when do they get time to write a letter, let alone an essay, or read a book? Call me an old fogey, but a person who cannot do those things seems to me not quite civilised.