Signs intended to enforce smoking bans may have a counter-intuitive effect on people addicted to tobacco, according to psychologists.
And no smoking signs may have an “ironic effect” and actually be driving more people to light up, a study suggested.
It found the cumulative effect of messages related to smoking could ultimately increase the recipient’s craving for tobacco.
Researcher Brian Earp, from Oxford University, presented the findings at the British Psychological Society’s annual meeting in Glasgow.
He said: “You get ironic effects when you couple information that people perceive with negation. When I say don’t think of a pink elephant, I’ve just put the thought of a pink elephant in your head.
“A lot of public health messages are framed in a negative way: say no to drugs, don’t drink and drive, no smoking.
“No smoking signs in particular are everywhere. If you’re a smoker walking down a street you’re likely to pass five or six of these signs in windows or on doors. If you have a chronically positive attitude to smoking this could boost your craving.”
Some smokers, without being aware of it, react to the signs by thinking of and wanting cigarettes.
A group of smoking volunteers from a town in New England, US, were shown several photographs, some of which included a no smoking sign in the background or on the periphery, while others had the signs edited out.
Mr Earp’s team found that participants who had earlier been shown no smoking signs were more drawn to smoking-related images such as ash trays and cigarettes. “It’s a significant effect which we think would have real life implications,” he added.