Washington, Aug 13 : Watching an action star walk along the ledge of a skyscraper makes us skip a heartbeat, as if we were risking our own life. Also, while reading a book that describes the same scene can give goosebumps. Now, a team of researchers has come up with an answer to explain why exactly this happens.
At the NeuroImaging Center of the University Medical Center Groningen of the University of Groningen (the Netherlands), Mbemba Jabbi, Jojanneke Bastiaansen and Christian Keysers compared what happens in our brains when we view the facial expressions of other people with the brain activity as we read about emotional experiences.
"We placed our participants in an fMRI scanner to measure their brain activity while we first showed our subject short 3s movie clips of an actor sipping from a cup and then looking disgusted," said Christian Keysers.
"Later on, we asked them to read and imagine short emotional scenarios; for instance, walking along a street, bumping into a reeking, drunken man, who then starts to retch, and realizing that some of his vomit had ended up in your own mouth.
"Finally, we measured their brain activity while the participants tasted unpleasant solutions in the scanner," Keysers added.
"Our striking result is that in all three cases, the same location of the anterior insula lit up. The anterior insula is the part of the brain that is the heart of our feeling of disgust," said Keysers.
"Patients who have damage to the insula, because of a brain infection for instance, lose this capacity to feel disgusted. If you give them sour milk, they would drink it happily and say it tastes like soda.
"What this means is that whether we see a movie or read a story, the same thing happens: we activate our bodily representations of what it feels like to be disgusted- and that is why reading a book and viewing a movie can both make us feel as if we literally feel what the protagonist is going through," added Keysers.
The study has been published in the open-access journal PLoS ONE.