Alzheimer's disease has been described as the great unlearning.

But what does it reveal about the nature of human identity?

What remains when memory unravels and how might such insights help Alzheimer's sufferers themselves?

We'll explore these questions with the psychologist, Alandine Steg.

He's led support groups with early Alzheimer's patients,

as well as a writing group he co-designed with the novelist, Don Delilo.

Alandine Steg has observed the early stages of Alzheimer's

as a time for giving memories away rather than losing them.

In the end, I think it's that they were making a statement about who they are

and the moment that they were in was such that it has this kind of resonance

that feels familiar to all of us on some deep level,

which is that we don't have an unlimited amount of time.

And we're going to run out of it.

And when you watch these people, you see people who are running out of time.

So there's almost something heroic, you know, like,

I'm going to tell you who I am before it's too late.

I'm going to tell you this story about picking lilacs from a tree with my mother.

You know, I'm going to, whatever it is, you know, a simple story like that.

Somehow has this kind of, it's elevated.

I'm Christa Tippett and this is on being.

Alandine Steg is a clinical psychologist in private practice in New York.

I interviewed him in 2009.

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