A leading scientist has indicated that social networking sites like Facebook and Twitter have created a generation obsessed with themselves, who have short attention spans and a childlike desire for constant feedback on their lives.
Baroness Greenfield, professor of pharmacology at Oxford University, believes the growth of Internet "friendships" - as well as greater use of computer games - could effectively "rewire" the brain.
This can result in reduced concentration, a need for instant gratification and poor non-verbal skills, such as the ability to make eye contact during conversations.
"What concerns me is the banality of so much that goes out on Twitter," the Daily Mail quoted Baroness Greenfield, former director of research body the Royal Institution, as saying.
"Why should someone be interested in what someone else has had for breakfast? It reminds me of a small child (saying): "Look at me Mummy, I'm doing this", "Look at me Mummy I'm doing that".
"It's almost as if they're in some kind of identity crisis. In a sense it's keeping the brain in a sort of time warp," Greenfield added.
The academic suggested that some Facebook users feel the need to become "mini celebrities" who are watched and admired by others on a daily basis.
They do things that are "Facebook worthy" because the only way they can define themselves is by "people knowing about them".
"It's almost as if people are living in a world that's not a real world, but a world where what counts is what people think of you or (if they) can click on you," she added.