Researchers at Newcastle University alternated hanging posters of staring human faces and posters of flowers on the walls of a cafe. They then counted the number of people who cleaned their plates and rubbish away after finishing their meal in both situations.
In a paper, which is published this week online in the American journal Evolution and Human Behavior, the research team, lead by Dr Melissa Bateson and Dr Daniel Nettle of the Centre for Behaviour and Evolution, describe their findings.
During periods when the posters of faces were on the walls, watching over the diners, twice as many people cleaned up, compared to the periods when the pictures of flowers were overlooking the diners, when more litter was left for cafe workers to clear away.
In a previous study in 2006 the same scientists looked at the impact of images of eyes on contributions to an honesty box in a tea room. They found that people put nearly three times more money in the box when there were eyes compared with flowers.
For this follow-on experiment, psychology student, Max Ernest-Jones, eager to explore whether the honesty box findings would extend to other forms of cooperation, spent many hours sitting inconspicuously in the corner of the café recording customers’ littering behaviour.
Dr Bateson, who led the research, said: “These findings reinforce the conclusion from our previous research, that the presence of eye images can encourage co-operative behaviour. We think that the images of eyes work by making people feel watched. We care what other people think about us, and hence we behave better when we feel we are being observed.
“We found that the impact of the posters was a lot greater at times when the cafe was quiet. This makes total sense, because we would expect real people to have the greatest effect on the feeling of being watched and hence swamp the effect of the posters during busy times.
“This study has implications for the fight against anti-social behaviour. For example if signs for CCTV cameras used pictures of eyes instead of cameras they could be more effective.”
The study is based on the theory of ‘nudge psychology’ which suggests that people may behave better if the best option in a given situation is highlighted for them, but all other options are still left open, so the person isn’t forced into one particular action. In effect you ‘nudge’ people into doing the right thing.
Dr Bateson added: “This study confirms that the display of images of eyes has broad potential as a ‘nudge’, not just because eyes grab attention, but because of more fundamental connections between the feeling of being watched and cooperative behaviour.
“Even painting a pair of eyes on a wall may be useful for preventing anti-social behaviour in quiet locations.”