People's moral judgment can be altered by disrupting part of the brain according to a U.S. study, AFP reported Tuesday.

Researchers at the Massachusetts Institute of Technology (MIT) disrupted activity in the right temporo-parietal junction (TPJ), located above and behind the right ear, an area usually highly active when we think about what we believe the outcome of a particular act will be.

The researchers disrupted the TPJ by inducing a current in the brain using a magnetic field applied to the scalp and asked study participants to read a series of scenarios posing moral conundrums.

In one scenario, a person called Grace and her friend took a tour of a chemical plant when Grace stops at the coffee machine. Her friend asks her to get her a coffee with sugar. A container by the coffee machine is marked 'toxic' but contains sugar -- Grace does not know that. She puts it in her friend's coffee anyway and her friend is unharmed.

Participants in the study, published in the Proceedings of the National Academy of Sciences, were asked to judge on a scale of one to seven if they thought what Grace did was morally acceptable. One ranks as “absolutely forbidden" and seven as "absolutely permissible."

Two experiments were conducted: during one, participants were asked to judge the scenarios' characters after magnetic pulses were sent to their TPJs for 25 minutes, and in the other they passed judgment while undergoing very short bursts of magnetic interference.

In both experiments, disrupting normal neural activity in the right TPJ switched off the part of people's "moral compass."

When it was disrupted, participants were more likely to judge failed attempts to harm another person as morally permissible than those participants whose right TPJs were not altered.