(AP) -- The two things that have brought Michael and Roslyn Lieb closer together couldn't be more different: Parkinson's disease and dance, one slowly taking away, the other giving back in ways they never imagined.
After tremors in his right arm and leg 11 years ago led to Michael Lieb's diagnosis with the debilitating brain disease, his wife became his caretaker. But two years ago, she developed a tremor, too. The diagnosis: Parkinson's.
"I couldn't believe it. It seemed incredible to me that we both should have the disease," he said. "It came as a real shock, a real downer."
"No one in either of our families has Parkinson's," she said. "It's come out of the blue for both of us."
Now retired, the couple still love to read, go the symphony and opera, and get together often with family and friends. Once a week, they head to an unusual Chicago dance class tailored for Parkinson's patients.
A nurse first recommended the Hubbard Street dance classes three years ago, and Michael Lieb figured he had nothing to lose. His wife went along - first to help Michael, now to benefit herself, too.
The tremors and stiff, awkward movements of Parkinson's hardly seem compatible with dancing. But exercise is sometimes recommended for Parkinson's patients, to improve flexibility, and brain specialists are investigating if dance offers something more.
For the Liebs, the answer is clear.
"It just lifts the spirits," said Roslyn Lieb, 69. "It does transport us, to a different planet where Parkinson's doesn't matter so much."
"We check our Parkinson's at the door and we're all one community, mutually supportive and we dance together," said her 71-year-old husband. "It's just a marvelous experience."
The free classes just west of downtown Chicago are offered by an internationally known troupe whose performances blend modern dance, jazz and ballet.
Sarah Cullen Fuller, who danced with Hubbard Street for seven years, launched the classes three years ago, borrowing the idea from the Mark Morris Dance Group in New York.
The classes have grown from half a dozen people to sometimes as many as 30 or more. Students include former educators, scientists, doctors "and everything in between," Fuller says.
These dancers wouldn't be mistaken for Baryshnikov, Martha Graham or even the amateurs on TV's "Dancing with the Stars." But their moves are just as stirring, in a less showy, poignant way.
Some are in wheelchairs or can barely move without their partners' help. During a recent class, a man stood behind his wife's chair, leaning down to gently stroke her immobile arms in time with the music. A pianist with two small drums fills the studio with a steady, soothing beat.
Fuller leads students through basic dance exercises - rhythmic arm-lifting, bending and foot-stomping - sometimes while they're seated in chairs, sometimes on foot, sashaying in a way with their partners across the dance floor.
"They assume that they're not dancers, whereas I see them as dancers. I don't see the disease - I try not to. I try not to let it permeate the room. But I also see them working through it and pushing" to find new ways of moving, Fuller said.
Michael Lieb is a renowned scholar of the English poet John Milton and was a longtime University of Illinois-Chicago professor; Roz worked as a public interest attorney. They are less severely affected by Parkinson's than some of their classmates. Their hands shake when they swing their arms toward the ceiling, and their sometimes halting strides across the floor aren't as long and graceful as Fuller's. But when the Liebs face each other in a sort-of do-si-do, smiling and rhythmically shifting their feet, there's no question that they're dancing.
The class has become a highlight of their week. Whether the benefits are physical, psychological, or both, Michael Lieb says dancing "has mobilized something in me to make me want to go on, and for as long as it's effective, I'll keep doing it."
Parkinson's involves a loss of brain cells controlling movement. Besides tremors, it can cause rigid, halting walking, slowed speech and sometimes dementia. Symptoms worsen over time and can be treated with drugs but there is no cure.
The disease affects about 1 million people nationwide, 6 million globally, according to the National Parkinson's Foundation. The cause isn't known but genes are thought to play a role.
Dancing, because it's accompanied by music, may offer benefits beyond other types of exercise for Parkinson's patients, including socialization for people otherwise isolated by their disease, said Harvard neurology professor Dr. Daniel Tarsy, director of the Parkinson's disease center at Boston's Beth Israel Deaconess Medical Center.
"When you hear music, it sort of drives the emotional parts of the brain," he said.
That may help bypass damaged brain cells in Parkinson's patients, making movement easier, he said. Tarsy is researching whether that means a real improvement in brain function.
Gammon Earhart, a Parkinson's researcher at Washington University in St. Louis, led a recently published study showing that twice weekly tango classes seemed to help Parkinson's patients walk more quickly and with less stiffness than patients who didn't dance.
The Hubbard Street class exercises include tango-esque strides across the dance floor, along with positions borrowed from ballet, and more free-form modern dance moves.
Michael Lieb says he used to lack the energy and will to do some of the dance exercises. He retired from teaching because Parkinson's stole his stamina, his impulse to share his ideas and "to excite a class without undue shaking," Lieb said in the subdued, flat-sounding speech that sometimes comes with disease.
The couple has been married for 48 years. With her short coifed silver hair, and his glasses and graying beard, they seem dignified yet down-to-earth and philosophical about how the disease is changing their lives.
Parkinson's is forcing them to sell the spacious suburban Oak Park home where they raised two sons and entertained their three grandchildren; they've bought a condo where they won't have to navigate stairs.
"No one knows what the future may hold" and that is what's most frightening, Roslyn Lieb said, her voice breaking. "I have a goal of dancing at my grandchildren's weddings."
Together "we represent one unit, one truly healthy person who is becoming more and more unhealthy as time goes on," her husband said.
"But that's OK. We're facing up to it and we're enjoying each other in a way, and loving each other in a way that would have been impossible without the disease."
More information: Hubbard Street Dance Chicago: http://www.hubbardstreetdance.com