Funny business

“IF YOUR seat belt is a bit uncomfortable, it might be because you’re sitting on it,” quips the Alaska Airways flight attendant during the passenger safety announcement. The recording became a hit on YouTube, a video-sharing website.

Advertisers have long known that humour can help to sell things, but more companies and public bodies now recognise that it can also help customers pay more attention to safety drills. Airlines from Australia to America have duly taken note.

Public-service announcements during the second world war used plenty of jokes, making light of the hardships of rationing. But as the numbers of announcements increased, they became gloomier. Some, such as Britain’s “Don’t Die of Ignorance” campaign against HIV/AIDS in the late 1980s, took their moribund tone from horror films. Such efforts can backfire. According to Ashesh Mukherjee and Laurette Dubé of McGill University, terrifying films can prompt defensive responses that reduce their persuasive effect.

But humour seems to fare better. Research by Jim Lyttle, then of York University in Canada, suggests that jokes affect how people process information—if they laugh at something, they are less likely to disagree with it. So serious subjects are being treated with levity—including in India, where an anti-rape campaign tells women, “It’s your fault,” mocking excuses for sexual violence. Similarly, an American anti-homophobia broadcast parodies scaremongering adverts of the 1950s to inform audiences that they may well have a homophobe living in their street.

Jokes can make serious messages more effective. Mr Mukherjee and Ms Dubé found that funny anti-skin-cancer ads made people 20% more likely to use sun cream. And amusing anti-AIDS messages in Norway were more effective than the austere Canadian offerings.

But not everything can be laughed off. Researchers at the University of Pennsylvania suggest that joking about drugs may glamorise their use rather than discourage it. And people scared of flying may find fun announcements inappropriate. WOW air, an Icelandic airline, had to tone theirs down after complaints from passengers. Even so, a video of crew and passengers solemnly performing the “Harlem Shake”, a group dance, is doing the rounds.