This is Hidden Brain. I'm Shankar Vedantam.

Early one morning in March, 1964, a woman named Kitty Genovese was on her way home from the bar where she worked.

She parked her car and was walking toward her apartment building when a man attacked and killed her.

Over the years, Kitty Genovese's murder has been the focus of countless books, movies,

and psychology research papers. It drew attention not only because it was a grisly crime,

but because it supposedly explained a deep flaw

in human nature. The New York Times published an article that said dozens of people saw the

murder or heard Kitty Genevievee screaming for help, but no one intervened. When someone did call

the police, it was too late.

In the decades that followed, the case came to symbolize a psychological phenomenon known as the bystander effect.

When lots of people see something is wrong, the theory goes,

each person wrongly assumes someone else will step up to help.

The net effect is that as the number of potential helpers increases,

the number of people who actually help decreases. In recent years, psychologists and journalists have

re-examined the facts of the Kitty Genevievee's story and walked back some of the claims. The Times

has said that its initial reporting was flawed and exaggerated. I think the power of the Kitty Geneovese story lies in the fact that in everyday life,

we all notice that we are not as helpful and brave as we would like to be.

We look away from people who are suffering.

We cross the street to avoid an altercation.

Even when the stakes are low for personal safety, we don't extend a hand to others who need help.

This week on Hidden Brain, the curious psychology behind a phenomenon that is all around us,

and how understanding a quirk inside our minds

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