As it emerges that disgraced cyclist Lance Armstrong is to take to the sofa on Oprah Winfrey's TV show, Channel 4 News asks what does a celebrity gain from a very public confession?

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Mr Armstrong, who was stripped of his seven Tour de France titles after cycling governing bodies ruled he had headed up a "sophisticated doping operation", will appear in a "no holds barred interview" with the US chat show legend on Thursday 17 January.

He will appear on Oprah's Next Chapter, the successor show to The Oprah Winfrey Show, to "address the alleged doping scandal, years of accusations of cheating, and charges of lying about the use of performance-enhancing drugs throughout his storied cycling career", the Oprah Winfrey Network said in a statement.

Ms Winfrey interviewed the cyclist, who resigned as chairman of his cancer foundation Livestrong following a damning report by the US Anti Doping Federation, at his home in Austin, Texas.

Mr Armstrong's reasons for doing the interview are as yet unclear, and what he will say has not been revealed. However, the New York Times did run a piece on Saturday saying that Mr Armstrong's representatives have reached out to the US Anti Doping Agency to see if the lifetime cycling ban which was imposed on him could be mitigated if he made a confession. The extent to which Ms Winfrey's sofa will be used as a confessional remains to be seen.

Baring all

However, Oprah's studio has become the go-to place for US celebrities with something to get off their chest (see box, below).

Celeb confessional - Oprah's guests
Michael Jackson: vitiligo was a relatively unheard of condition until the secretive popstar said it was the reason for his changing complexion in an interview in 1993.
Tom Cruise: the Hollywood superstar jumped up and down on Oprah's sofa as he declared his love for Katie Holmes in May 2005.
Whitney Houston: the popstar revealed the extent of her drug addiction on the show in September 2009.

Honey Langcaster-James, a celebrity psychologist, told Channel 4 News that the reasons for a public confession can be emotional, or strategic.

"Often you find out that a particular celebrity has wanted to come clean for quite some time, but they have been advised not to by their PR teams," she said.

"They often chose to do it because they cannot hold onto the skeleton any longer. There is an emotional benefit, and afterwards they can feel a asense of relief even if what has been revealed is not very flattering to them.

"Another reason can be because the time has been chosen by a PR team to try and reclaim the celebrities reputation, and try and make them appear honest and trustworthy."

People do this kind of confession in order to present themselves as the victim in some way - behavioural psychologist Jo Hemmings

Authenticity?

Indeed the presentation of a persona can be a part of a celebrity's survival, Dr Kirsty Fairclough, a lecturer in media and performance at the University of Salford, said.

"The voyeuristic celebrity culture that exists makes the celebrity confessional the perfect tool for the negotiation between celebrity and public," she told Channel 4 News.

"The celebrity presents their emotional limitations or damaged personality which is deemed authentic and this is then traded for the continuation of the relationship between the celebrity and his or her fans."

There are certainly no guarantees that the celebrity will emerge any better off - Dr Kirsty Fairclough

This would suit Lance Armstrong, behavioural psychologist Jo Hemmings believes, because he is a "showman".

"(By going on Oprah) he will be able to blur the edges of his alleged wrongdoing," she said. "People do this kind of confession in order to present themselves as the victim in some way."

There is another blurring effect, argues Ms Langcaster-James - Oprah's "halo effect". "Everything she touches turns to gold," she said. "They will be hoping that some of her shine rubs off on them".

Redemption?

However, if Mr Armstrong is making a confession on Oprah's show, he is not guaranteed redemption, argues Dr Fairclough.

She said. "This type of interview is very clearly a performance of sorts, however contrived or not. They are often highly stage-managed and manipulative in order to attempt to revive or redeem a career or purely for damage-limitation.

"It does not guarantee redemption and indeed can backfire. In a celebrity culture where the public can alter the intended persona of a celebrity via social media, there are certainly no guarantees that the celebrity will emerge any better off."