This is Hidden Brain. I'm Shankar Vedantam. In Chinese mythology, Meng Po is sometimes known as the goddess of oblivion.

She polices the land of the dead and has a special responsibility. She makes sure that souls on their way to being reincarnated do not remember their past lives.

To ensure this, she prepares a soup with five ingredients. Her five-flavored soup of oblivion produces immediate and permanent amnesia.

The soul can now proceed to be reincarnated with no memory of previous lives.

There are rare occasions when spirits fail to drink the five-flavored soup,

and when these souls are reincarnated, they become humans who can remember their past lives.

Nearly every culture in the world has stories and legends about memory and forgetfulness.

Our ability to remember long ago events is a signature accomplishment of the brain.

Our inability to remember important things is an endless source of frustration.

Today on the show, and in a companion story on Hidden Brain Plus, we examine the science of forgetting.

We look at why our minds hold on to some memories for a lifetime, but discard others

within seconds.

And we answer a question many people ask themselves.

Is my forgetfulness a sign that something is wrong with me?

Forgetting to remember and remembering to forget this week on Hidden Brain. In Charles Dickens' novel, Great Expectations, we are introduced to the character Miss

Havisham. Many years earlier, she was jilted at the altar on her wedding day. She becomes obsessed with this moment and cannot move on from it.

She surrounds herself with reminders of that day, wearing her wedding dress and keeping the clock stopped at the exact moment of her wedding.

In so doing, she becomes consumed with sadness.

She becomes a prisoner of her own memories.

The memories we carry say a lot about who we are and how we see the world. At University College Dublin, psychologist Kira Green

studies how memories are formed and the roles that both remembering and forgetting play in our lives.

Kira, welcome to Hidden Brain. Hi, Shankar. Thanks for having me.

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