Party political leaders hope that television viewers concentrate on their words and their carefully choreographed delivery as they present their election manifestos.
But Geoff Beattie, professor of psychology at Manchester University, believes that we can learn much more about what politicians really think if we focus on their body language.
As the election gathers pace, he will be presenting tips on what to look for in Body Politic , to be screened every day as part of ITV's news programmes.
Professor Beattie, author of a book on the subject and resident psychologist on Channel 4's Big Brother , suggests that politicians' hand gestures and facial expressions often tell a different story from what they are saying.
Tony Blair's sudden fixed smile may be designed to exude confidence, but his expression a quarter of a second after it drops leaves a different impression.
Michael Howard, the Tory leader, seemed unflustered during his manifesto launch, but the stabbing motion of his pointing finger suggested otherwise.