London: People are less likely to drop litter if it has printed eyes on it, according to the researchers at Newcastle University in Britain.
An image of watching eyes reduced the odds of littering by around two thirds.
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. In effect, you 'nudge' people into doing the right thing.
"Our work shows that the presence of eye images can encourage cooperative behaviour and we think this is because people feel they are being watched," said Daniel Nettle from the Centre for Behaviour and Evolution.
"As we care what other people think about us, we behave better and more honestly when we feel we are being observed," Nettle added.
In an experiment, researchers printed two leaflets, one featuring a prominent image of watching eyes and the same leaflet with the eyes obscured.
Even with no mention of littering, the simple image of the eyes deterred people from dropping the litter.
"This is reinforced by our results as we show that we didn't need to include a message about littering, people know it is antisocial so it was enough to have an image of the eyes," Nettle said.
The findings showed that just 4.7 percent of people dropped the leaflet with eyes compared to 15.6 percent of the control leaflets.
In second experiment, the effect was only present when there were no other people in the immediate vicinity as when other people are present you are less likely to behave in an anti-social manner.
"In the fight against anti-social littering, this study could be a real help. Fast food retailers might want to think about using it on packaging to discourage people discarding the wrappers," said another researcher, Melissa Bateson.
"The flip side is, for those handing out leaflets, it could help people take in the messages are they are less likely to throw away a flyer with eyes on," Bateson concluded.
The paper was published in the journal PeerJ.