We all know we feel different when telling the truth or lying.

Now researchers in Japan have identified a part of the brain that becomes more active when people are being dishonest.

The group at Kyoto University subjected a group of 28 Americans to a coin toss test.

The subjects were told they could keep the money if they correctly predicted heads or tails.

Lead researcher Nobuhito Abe says scans showed a part of the brain called the nucleus accumbens became highly active when people lied about their predictions.

The nucleus accumbens responds when feelings of desire are rewarded.

Abe says the study shows people with strong desires are more likely to lie.

The research is the first to show how individual differences in the nucleus accumbens may affect our propensity to be honest.