Forgiveness and the RTPJ Region of the Brain

If someone causes harm, but it was an accident, how much blame should be placed on the person?If a person swerves to avoid a cat and accidentally runs over a pedestrian? Is the person to blame?

What if a person puts poison into someone’s coffee thinking that it was sugar, is the person guilty? And how much blame should be placed on the person.

That last one was the question posed in the experiment by Department of Brain and Cognitive Sciences at Massachusetts Institute of Technology. In order to answer this moral question, a person needs to be able to ascertain intention and attribute “false belief” (the ability to recognize that others can have beliefs about the world that are wrong or different from one’s own).

This area of study is known as the “Theory of Mind“.

Neuro-scientist, Rebecca Saxes, talks about this experiment in a TED talk video. The experiment is also written up in the paper titled “Innocent intentions: A correlation between forgiveness for accidental harm and neural activity“.

Massachusetts Institute of Technology researcher speaks with National Public Radio about this experiment (read and hear story here). This study is also published in the Proceedings of the National Academy of Sciences: Disruption of the right temporoparietal junction with transcranial magnetic stimulation reduces the role of beliefs in moral judgments.

The experiment revolves around a hypothetical story of Grace and her friend on tour in a chemical factory. There was a pot of coffee with some white power next to it. Grace’s friend wanted some sugar with her coffee. So Grace put some of the white power into the coffee. While Grace thought the power was sugar, the power actually was poison and caused Grace’s friend to become sick. The exerimental subjects was asked how much blame should Grace get for causing harm to her friend (even though it was unintentional)? Functional MRI (Magnetic Resonance Imaging) was also used to observe the subjects during the moral judgement. It was found that an area of the brain above the right ear known as the “right temporo-parietal junction” (RTPJ) lit up during the activity. The higher the activity in the RTJP, the less blame the subjects placed on Grace. In other words, the greater the activity in the RTJP, the more the person takes into account the fact that the act was an accident.

Next, the experiment used transcranial magnetic simulation (TMS) to send an electromagnetic pulse to the subject’s brain in order to temporarily disrupt the functioning of this brain region and now they found that people were less able to forgive Grace. So the ability to forgive accidental harm is dependent on the proper functioning of this RTPJ region of the brain.

Right Temporoparietal Junction Involved in Making Moral Judgement

There is another scenario. Let’s say that the white power is labeled poison, but it was really sugar. Grace gives the white power labeled poison to her friend. Even though nothing happened to her friend in this case, how much blame should Grace get? The typical response is that Grace should receive a lot of blame of giving something labeled poison to her friend. This is because Grace had the “intent to do harm” and that is morally unacceptable.  She got more blame than in the accidental case. This shows that intent plays a bigger role in moral judgment than the actual outcome.

However, when transcranial magnetic simulation was again used to disrupt the functioning of the RTPJ region of the brain. Now people placed less blame on Grace. As expected, the disruption of the RTPJ made people less able to take intent into account.

In order make proper morality judgments, the right temporoparietal junction of the brain needs to function properly.

Childhood Development and the false belief task

Given the importance of certain brain regions involved in moral judgment, it is not surprising that young children are not able to make moral judgment as well as adults because their brains are not fully developed.

When young children were asked which boy is more naughty: (a) the boy who accidentally broke 5 teacups, or (b) the boy who intentionally broke one teacup, they often will say that the one who broke 5 teacups is more naughty (even though it was unintentional).

We are not born with this ability to read other people’s mind and to take intention into account. It is slowly developed during childhood.

Somewhere between age 3 and 5 is when a child has develops the ability of recognize that other people can have different and/or wrong beliefs from their own. This is demonstrated in the “false belief task”.

A child is told this story. Ivan the pirate places his cheese sandwich on a treasure chest. Ivan goes away for a while and during that time, the wind blew the sandwich onto the grass. Another pirate named Joshua comes along and places his own cheese sandwich on the chest and then goes away. Now when Ivan comes back, which sandwich will he take? His actual sandwich that is on the grass, or Joshua’s sandwich that is on the chest.

A child of three will say Ivan will take the sandwich on the grass (because that is actually Ivan’s sandwich). A child of five will realize that Ivan did not know that his sandwich fell onto the grass and will say correctly that Ivan will take the sandwich that is on the chest.

Now when asked should Ivan be blamed for taking Josuha’s sandwich that was on the chest. A child of five would say yes. But a child of seven will say no because Ivan did not intent to take Joshua’s sandwich. Ivan thought it was his own sandwich that he is taking.