Today's guests include Dr Campbell Bunce, from Xenova, who joins us to talk about vaccines to prevent nicotine and cocaine addiction, Cambridge University's Prof. Barry Everitt, who works on the brain mechanisms of addiction, and Prof. Lawrence Whalley, from the University of Aberdeen, who has been looking into how smoking can dimish brain power as you age. Also joining us on the show is Prof. Mark Griffiths, from Nottingham Trent University, the UK's only professor of gambling addiction, who asks whether gambling can genuinely be considered an addiction, like nicotine or heroin.