How 'Big Brother' can make you barmy

While most of us think the contestants on Big Brother must be slightly odd to enter the house in the first place, a leading psychologist has warned they may be barmier still by the time they leave.

Yesterday, Oliver James, the psychologist and broadcaster, called on TV executives to pay for a long-term study into the effects of reality shows on their participants.

Programmes such as Channel 4's Big Brother use psychologists to assess who would be suitable for the show and then offer aftercare when contestants have finished taking part.

But Dr James told a special conference on reality programmes at the Edinburgh Television Festival that "emotionally vulnerable people" were continuing to take part.

"The results of a study could be used to screen out vulnerable people," he said. "It's not just namby-pamby psychobabble to say that the broadcasting industry should fund this study."

His worries seem to be backed up by comments from Narinder Kaur, dubbed "Nasty Naz" by the tabloids for bitching about her housemates. Ms Kaur said: "I came away from this experience thinking, 'Oh my God, did I really say that?' I've found it more humiliating coming out than being in there."

Vanessa Feltz, the television presenter, took part in Celebrity Big Brother earlier this year and was seen frantically scribbling on a table, prompting fears she had had a breakdown on television. "I looked like Jack Nicholson in The Shining," she claimed.

Shortly afterwards she was back to her old self, she said, arguing that selective editing had distorted how she appeared: "There is nothing less real than reality TV," she claimed.

A poll into the effects of such programmes shows young people taking them very seriously, however. It found 24 per cent of 15- to 24-year-olds called themselves "obsessed" by shows such as Big Brother, often shaping their social lives around watching the programmes.