Seeing someone perform an act of kindness can warm your heart. That feeling has a name -- it's called moral elevation, and it's that warm-and-fuzzy-on-the-inside sensation you get when you're in the presence of true human goodness.
The feeling helps to explain why kindness is, quite literally, contagious. Studies have found that this natural high makes people want to behave more altruistically towards others.
New research published in the journal Biological Psychiatry aimed to find out what moral elevation actually looks like in the brain and body. Researchers measured the brain activity and heart rates of 104 college students while they watched videos depicting either heroic acts of kindness or humorous situations.
When the students were viewing the heroic acts, activity in both the sympathetic and the parasympathetic nervous system peaked -- an unusual combination that suggests both a fight-or-flight response and a calming, self-soothing response. When they were watching the amusing videos, there was no activation in either system.
“This is a really uncommon pattern, where you see both of these systems recruited for one emotion,” Dr. Sarina Saturn, a psychologist at Oregon State University and one of the authors of the study, told the Greater Good Science Center.
This may be because viewing a compassionate act requires us to witness suffering, which enacts a stress response and activates the sympathetic nervous system. Then, once we see the suffering alleviated through an act of kindness, our heart feels calmed and the parasympathetic nervous system is activated.
The researchers also found that activity in the medial prefrontal cortex of the brain, an area that deals with empathy and the ability to predict others' thoughts and behavior, lit up in scenarios involving someone being helped after they were physically injured -- but not in the act of kindness that was performed on someone who was not injured. That suggests that this brain region likely has some role in moral elevation, but further research is needed to determine exactly what the role is, and whether it's only activated when we see someone in pain.
Want a little moral elevation of your own? Try watching this emotional scene from It's A Wonderful Life, psychologist Jill Suttie advises:
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