A Moment of Science

Where Does The Brain Process Moral Decisions?

Scientists hope that by figuring out how the brain behaves, we'll be able to understand how people with different backgrounds reach different conclusions.

brain on a table

Photo: karmaOWL (Flickr)

Making a decision... your brain is working hard!

Yaël And Don Try An Experiment…

Don: Yaël, suppose there’s a trolley that’s about to run over five people. Do you flip the switch that will steer the trolley onto a different track if that means only one person will die?

Yaël: I sure would.

Don: Okay, now what if the only way you can save those five people is by pushing the stranger next to you into the trolley’s path?

Yaël: Yuck, Don. That would be wrong.

Don: You know, Yaël, most people, when asked this question, answered the same way. And moral philosophers and psychologists have been trying to figure out why. After all, in both cases, one person dies to save five.

Inside The Science

In one study, scientists discovered that these two scenarios are processed by different parts of the brain. Flipping a switch, because it’s more impersonal, activates the part of the brain associated with memory. But the more personal scenario that requires actively killing a person activates the part of the brain associated with emotions.

Scientists speculate that a lot of our gut reactions to moral dilemmas may be affected by our upbringing. After all, as children we internalize the emotional reactions of those around us and store them in emotional brain circuits. Then, later, when we encounter a moral problem, these automatic gut feelings guide our decision-making.

Scientists hope that by figuring out how the brain behaves when people wrestle with difficult issues, we’ll be able to understand how people with different backgrounds reach different conclusions on when it’s okay to take a life. And everyone knows we could use a little more understanding

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