Children who use social networking sites such as Facebook risk getting lower marks at school, a US study has claimed.

Children are also likely to have narcissistic tendencies, suffer from behavioural problems, and display signs of depression and anxiety, the report by psychology professor Larry Rosen from California State University discovered.

Speaking at the 19th Annual Convention of the American Psychological Association, he said: "While nobody can deny that Facebook has altered the landscape of social interaction, particularly among young people, we are just now starting to see solid psychological research demonstrating both the positives and the negatives."

He also said that the amount of media consumed influenced how well they performed as students. "If they checked Facebook just once during 15 minutes, they were worse students," he said.

Posted by Robert Mair on 10.8.11 Please send your comments on this article to: penny.hosie@pavpub.com