JIM LEHRER: Next: a unique program that brings together dancers and people living with Parkinson's disease.
Special correspondent David Iverson tells the story.
DAVID IVERSON: The Mark Morris Dance Center occupies a busy corner of Brooklyn. It's home to one the best-known modern dance companies in the world, where the physical defines the art.
But it's also home to a different group of dancers, where the physical defines a disease: Parkinson's.
DAVID LEVENTHAL, Mark Morris Dance Group: Our society tells us again and again that there are people who can dance, and there is everybody else, who shouldn't even bother, and I think that's such a tragedy.
DAVID IVERSON: David Leventhal and John Heginbotham have performed lead roles in some of the Mark Morris Dance Company's signature works. But they also teach some of those same moves to people with Parkinson's, creating both a unique class and a special community.
Mary Good (ph) was diagnosed with Parkinson's two years ago.
MARY GOOD, sufferer, Parkinson's Disease: The world judges us by how we look. And Parkinson's -- people with Parkinson's have really a look that people shy away from.
DAVID IVERSON: Is the class, then, a place where you're not judged?
MARY GOOD: That's exactly right. That's exactly right.
JOY ESTERBERG, sufferer, Parkinson's Disease: It's one of those situations where everybody is in the same boat.
DAVID IVERSON: Class member Joy Esterberg (ph) has had Parkinson's for seven years, but this class has given her something new.
JOY ESTERBERG: It's given me a community that you don't have in New York, for the most part. This community is like being in a small town.
JOHN HEGINBOTHAM, Mark Morris Dance Group: My impression is that many people with Parkinson's feel like they are outside of the human experience. And dance is a huge part of the human experience. And so, to come in and dance, you're human again.
DAVID IVERSON: At a meeting before the class begins, the cardinal symptoms of Parkinson's are often apparent: a hand that shakes, muscles that stiffen. But when class starts, symptoms often seem to slip away.
Class member Reggie Butts (ph):
REGGIE BUTTS, sufferer, Parkinson's Disease: When the dance class is going on, there are no patients. There are dancers.
DAVID IVERSON: It's a phenomenon that neurologist Dr. Claire Henchcliffe finds striking.
DR. CLAIRE HENCHCLIFFE, neurologist, New York-Presbyterian Hospital/Weill Cornell Medical Center: It's fascinating to see people who may have walked in slowly and sat down slowly and stood up slowly, and then, when the music comes on, they really just get going.
DAVID IVERSON: But it's not just the music and motion that's helpful. With Parkinson's, everyday actions like stepping and reaching take greater focus and concentration, which is exactly what dance demands.
DR. CLAIRE HENCHCLIFFE: You have to learn a complex series of steps, for example.
DAVID LEVENTHAL: I'm starting out with my palms facing me, and I'm going to rotate my hands, so my palm is now facing down.
DR. CLAIRE HENCHCLIFFE: There are pauses. There are turns. There are points where you go backwards. There are points where you mirror what your partner is doing. It has the physical component, but I think it also has the cognitive component.
DAVID LEVENTHAL: In dance class, the mind and body are constantly working together. You know, dancing is the ultimate mind-body connection.
DAVID IVERSON: Dance requires mind and imagination, focus and physicality. So does living with Parkinson's. It's grace that's hard-won.
JOHN HEGINBOTHAM: To be in control of your own movement and making it pleasing to yourself is a wonderful thing.
DAVID LEVENTHAL: Toss the flower petals.
REGGIE BUTTS: It's liberated a part of me, created a sense of freedom, a sense of creativity.
DAVID IVERSON: Perhaps that's why this isn't a class people skip. Reggie Butts is here just out of the hospital. His wife, Bobbi (ph), never misses either.
BOBBI BUTTS: The movement of butterflies and birds and throwing flowers. With dance, you soar.
JOY ESTERBERG: It's really like -- like bliss, in a way, because there is no constraint. If it's physical, and you extend your arm, you have an ideal sense of what an extended arm looks like. It doesn't look like this. But, if you try to do it, and, in your mind's eye, you are feeling it and doing it utterly to the extent that you can imagine it, then you are there.
DAVID IVERSON: And when you're there, Parkinson's isn't, at least not in the same way, which is why Dance for Parkinson's, as it's officially known, is now stretching beyond its Brooklyn borders.
DAVID LEVENTHAL: The best thing to plan around would be our regular Dance for P.D. class.
DAVID IVERSON: And David Leventhal, who this year won a New York Dance and Performance Award honoring his storied dance career, is leaving his performance life behind to devote all his time to Dance for Parkinson's.
DAVID LEVENTHAL: Now I spend a lot of the week on conference calls, which is something I never imagined. We have classes right now in about 14 states, from California to Washington State to Texas -- Houston, Texas -- all the way down to Florida. There are three classes down there.
This class has given me a completely new and welcome understanding that movement is everybody's right, that we're all entitled to move, we're all entitled to dance in the most natural, free, joyous way.
DAVID IVERSON: Joy, it's not a quality you associate often with Parkinson's. And, yet, it is what you see here. There are people in this class whose condition limits how they move, but not their smile or spirit.
DR. CLAIRE HENCHCLIFFE: We don't as yet know how to measure that objectively, and someone's sense of happiness, and how that affects their Parkinson's disease. We don't know how to measure joy or happiness. But we should try.
DAVID IVERSON: And if you could measure joy in this corner of Brooklyn, you would also find that what you give, you receive, and that every bit of it is shared.