A new study has found magnetic fields can be used to confuse a region in the brain that controls a person's sense of morality.
Using a powerful magnetic field, scientists are able to scramble the moral centre of the brain, making it more difficult for people to separate innocent intentions from harmful outcomes.
The research, which appears this week in the journal Proceedings of the National Academy of Sciences, could have big implications for not only neuroscientists, but also for judges and juries.
"It's one thing to 'know' that we'll find morality in the brain," says Dr Liane Young, a scientist at Massachusetts Institute of Technology and co-author of the article. "It's another to 'knock out' that brain area and change people's moral judgments."
Before the scientists could alter the brain's moral center, they first had to find it.
Young and her colleagues used functional magnetic resonance imaging to locate an area of the brain known as the right temporo-parietal junction (RTPJ), which other studies had previously related to moral judgments.
While muscle movement, language and even memory are found in the same place in each individual, the RTPJ, located behind and above the ear, resides in a slightly different location in each person.
Good or bad intentions
For their experiment, the scientists had 20 subjects read several dozen different stories about people with good or bad intentions that resulted in a variety of outcomes.
One typical story was about a boyfriend who leads his girlfriend across a bridge. In some versions, the boyfriend harmlessly walked his girlfriend across the bridge with no ill effect. In other cases, the boyfriend intentionally led the girlfriend along so she would break her ankle.
The subjects used a seven point scale - one being forbidden and seven completely permissible - to record whether they through the situation was morally acceptable or not.
While the subjects read the story, the scientists applied a magnetic field using a method known as transcranial magnetic stimulation. The magnetic fields created confusion in the neurons that make up the RTPJ, says Young, causing them to fire off electrical pulses chaotically.
The confusion in the brain made it harder for subjects to interpret the boyfriend's intent, says Young, and instead made the subjects focus solely on the situation's outcome. The effect was temporary and safe.
When no magnetic field was applied, the subjects focused more on the boyfriend's good intentions, rather than a bad outcome. When a magnetic field was applied to the RTPJ, the subjects consistently focused on a bad outcome, rather than the intention, and rated the story as more morally objectionable.
The scientists didn't permanently remove the subject's moral sensibilities. On the scientists' seven point scale, the difference was about one point and averaged out to about a 15% change.
It's not much, says Young, "but it's still striking to see such a change in such high level behaviour as moral decision-making."
Young also points out that the study was correlation; their work only links the RTJP, morality and magnetic fields, but doesn't definitively prove that one causes another.
The research could have powerful implications not just for neuroscientists, but for lawyers as well. Everyday jurors are asked to weigh a person's actions against their intentions.
This new study won't transform the legal field, says Dr Owen Jones, a professor of law and biology at Vanderbilt University, but it could "enable sophisticated judgments about responsibility, harm and appropriate punishment."
"This study and other recent studies like it are enabling us to peer into the very brain activity that underlies and enables legal judgments," says Jones. "Understanding how legal decisions actually work is a potentially important step toward helping decisions be as fair, just and effective as they can be."
What the new research won't do is allow a jury, or even an individual, to unwittingly manipulate favour towards prosecutors or defendants. Because it was so obvious that the magnets were turned on, it is unlikely that a person or a group, like a jury, could be swayed to consider a criminal outcome instead of intent, says Young.
Magnetic fields made people judge outcomes more than intentions. Whether it's possible to do the opposite, making people focus more on intentions than outcomes, Young doesn't know.