Refusing a bribe elicits a stronger emotional response than accepting one, a study has found, offering hope of developing novel ways to tackle corruption.

The researchers studied the behaviour of 93 people playing an economics game involving bribery. They found that 19 per cent of participants rejected a bribe, and these respondents showed a greater emotional reaction to the situation than those who took the money.

This signals that bribery involves more-complex moral and emotional issues than just greed, the authors suggest.

"We based our study on the theory that people only care about money," says Tarek Jaber-López, a behavioural scientist from Jaume I University in Spain. "However, the results show that almost one-fifth of the subjects preferred to be more prosocial and chose a quality transaction rather than receiving a bribe."

The study was based on a game in which participants represented two firms simultaneously submitting sealed bids to an official. Players had the option of offering bribes to the official, also represented by a participant, to ensure their bid is chosen.

To assess participants' emotional responses when accepting or refusing bribes, the study used the electrical conductance of moisture on human skin to measure the activity of sweat glands on their hands.

"The participants who choose to be honest suffer more emotional arousal than the ones who accept the bribe," says Jaber-López.

He explains that being honest means losing money, but reaping a moral reward. When participants were asked about their emotions after the test, they said they felt good about having carried out a socially beneficial act.

Female participants were more likely to offer a bribe than their male counterparts, Jaber-López adds.