What should happen to Cliven Bundy

How fear makes us good or bad

When Abigail Marsh was 19 years old, a dog ran in front of her car on the highway. She dodged, skidded, and found herself on the opposite lane - and her engine wouldn't start. On the other side of the highway, another driver saw her flashing warning light, pulled over and ran to her aid. He pushed her into the passenger seat, restarted the engine, and drove her to safety. Then he disappeared into the night. She never saw him again.

What makes someone risk their life for someone they have never met before? And why do other people intentionally cause suffering and seem unrepentant? These are questions Marsh - now a lecturer in psychology and neuroscience at Georgetown University - wanted to answer. In her new book "The Fear Factor" The fear factor) she sets out her theory of how an ancient part of the brain evaluates and reacts to fear.

A stranger risked his life to keep you safe when you were a teenager. How has that affected the path you have taken in your life?

The combination of a situation in which I almost died and a stranger who saves me was an experience that moved me very emotionally. It was hard to get that out of my mind. What stuck the longest was the fact that a total stranger saved me. It seemed so unlikely - I couldn't imagine taking such a risk to help someone I'd never met.

I had this excruciating need to understand why someone would make such a decision. This mystery must have been the engine that drove me.

How did this question become your research area?

When I look back, it becomes clear to me that the common thread in my research has been an effort to understand why people want to help other people. This led me to do laboratory research on altruistic decision making. But you can't put people in a lab where they have to make life and death decisions. So, for my research after my doctorate, I chose people who clinically lack prudence and compassion.

We performed brain scans of teenagers with psychopathic traits while showing them pictures of frightened faces. We discovered that in a part of the brain called the amygdala - an evolutionarily old area involved in many emotional and social behaviors - there were few responses. As a contrast, I chose kidney donors for an examination because their behavior is most unequivocally altruistic: with a stranger there cannot be a mutual give and take.

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