In what is claimed to be the first snapshot study in Britain of computer game-playing by adolescents, 20 per cent of 12- to 16-year olds could be classed as 'addicted' to the games - 7 per cent to the point where they play for 30 hours or more a week.
'More worrying,' Dr Mark Griffiths of Plymouth University told the British Psychological Society's London conference, 'was that approximately one in five players admitted aggressive behaviour as a direct result of their playing'.
The findings are based on a questionnaire answered by 387 12-to 16-year-olds at an Exeter school. The study found that all but five of the children had played computer games, almost one-third played every day and three-quarters played for at least an hour at a time.
Seven per cent of the sample, however, played for more than 30 hours a week, Dr Griffiths, who undertook the study with Nigel Hunt, said. 'Regardless of whether you think computer games are a good or a bad thing, for an adolescent that is virtually all their leisure time, and if it goes on only for a period, it must be detrimental to their educational or social development.'
Across England and Wales, Dr Griffith's figures would translate into 200,000 12- to 16- year-olds spending that much time on computer games.
One in eight of the children said they played their favourite game because of its violent content, 'the first time it has been reported that people say they play the games because they are violent' - and one in five reported that they became more aggressive as a result of playing games which ranged from combat-style action such a Streetfighter 2 to puzzler games such as Tetris.
Using measures normally used to study gambling, one in five of the children were classed as 'addicted' to the games, with one in four having been addicted at some point in their lives. One in three of the children described the games as addictive, 11 per cent saying they played 'because they could not stop'.
Dr Griffiths said parents should not worry too much. 'For the majority, computer games are perfectly harmless and can be a source of great fun while some are educational.'
But games should be classified to carry warnings where they were violent, he said.
'We shouldn't have censorship, but children are a vulnerable section of society and are at an age where they can be psychologically manipulated and where attitudes can be fostered.
'A lot of these games have women cast in victim roles, where violence is seen as a good thing, and there is racism and sexism in them. If those kind of images are fostered, that is not a good thing.' He did not accept that graphic mutilation in some computer games was of the harmless Tom and Jerry-type humour.
But more research was needed to establish if particular games were more likely to make people aggressive.Reuse content