Can films help us understand anxiety as a clinical condition? Yes, says Jonathan Keane, film curator for the Mental Health Foundation's first anxiety arts festival. "The history of film," he says, "is the history of anxiety. At a screening of the Lumière brothers' early film The Arrival of a Train at La Ciotat, people ran out screaming: they thought the train was coming right at them. But film doesn't just make us feel anxious: it also stages anxiety, and helps us to understand how it works."