MIT neuroscientists can affect people's morals

Posted by Emma Woollacott

Scientists have discovered your moral compass - and it's just behind your right ear. MIT researchers have found they can successfully alter people's moral judgments by disrupting a specific brain region.

The right temporo-parietal junction (TPJ) is known to be highly active when thinking about other people's intentions, thoughts and beliefs.

The researchers induced a current in the right TJP using a magnetic field applied to the scalp, and found that the ability to make moral judgments needing an understanding of other people's intentions — for example, a failed murder attempt — was impaired.

The discovery is startling, since people are usually very confident and consistent in these kinds of moral judgments, says Liane Young, lead author of the paper.

"You think of morality as being a really high-level behavior," she says. "To be able to apply [a magnetic field] to a specific brain region and change people's moral judgments is really astonishing."

In one experiment, volunteers were exposed to transcranial magnetic stimulation (TMS) for 25 minutes before reading a series of scenarios and making moral judgments of characters' actions on a scale of 1 (absolutely forbidden) to 7 (absolutely permissible).

Next, TMS was applied at the moment when the subject was asked to make a moral judgment.

For example, people were asked to judge how permissible it is for someone to let his girlfriend walk across a bridge he knows to be unsafe, even if she ends up making it across safely. Here, a judgment based solely on the outcome would hold the man morally blameless, even though he intended to do harm.

In both experiments, the MIT researchers found that when the right TPJ was disrupted, subjects were more likely to judge failed attempts to harm as morally permissible.

They believe the TMS interfered with subjects' ability to interpret others' intentions, forcing them to rely more on outcome information to make their judgments.