There are holiday light displays, and holiday light shows. There are those meant to entertain, and those with a little more to impart.

A Plymouth man who learned at 47 that he had Young Onset Parkinson's Disease has created a holiday light show at his home called "P.D. Shimmers," to cast light on the degenerative disease.

"No one in my family had ever had it, and I've always thought it was a hereditary disease," said Mike Justak, whose diagnosis came in 2004. "I was angry about it, in denial; I didn't even want my family to know about it."

The light show is the result of a personal epiphany he experienced at a 2006 Easter Sunday church service. He resolved to do something positive, and felt compelled to become involved with the Michael J. Fox Foundation, which the actor created after his own diagnosis of Young Onset Parkinson's Disease at 30. That experience eventually led Justak to establish his own nonprofit foundation, Partnership's for Parkinson's.

The idea of a Christmas light display intrigued Justak, and some Internet research showed him the scope of what he could create. The software for creating his lights-to-music show was free "shareware" he found online.

After the initial eight hours he spent programming the first minute of music, he quit keeping track of the time, working an hour or two a day since Labor Day.

"The do-it-yourself website I use says, 'Remember: it's supposed to be fun!' so I try to keep that in mind," he laughed.

Justak has created a light show with snippets of various musical compositions, just enough to give the viewer a smile of recognition -- and in some cases, he hopes, some outright laughs.

The display features seven fresh-cut Christmas trees, 8,000 lights, hundreds of feet of extension cords and cables, and a 16-channel controller combined with music as diverse as the Blenders' "One Small Child" and "Dueling Banjos" from the movie "Deliverance," which accompanies the "Dueling Christmas Trees" segment of the show.

That fun aside, the 10-minute length of the program has special significance.

"Every 10 minutes, someone is diagnosed with Parkinson's Disease. I want people to think about that: In the time it takes them to watch and enjoy this holiday light show, another person has been diagnosed with Parkinson's," he said.

And one in five are under 50. "The incidence of people getting Parkinson's at a younger age is increasing," said Justak.

Acknowledging the "gallows humor" of the name of his show, "P.D. Shimmers," Justak says it ties in the "shimmering" of the lights as well as the widely known physical symptom of Parkinson's Disease, the tremors. Humor is a very important coping method, he said, noting with a laugh that "I call my fantasy [football] team 'Shake and Bake.'"

Like the holiday season itself, Mike Justak's message on his website is one of hope:

"I'm on a crusade. I'm more optimistic than ever. OPTIMISM? INDEED! Pass it on!"

Brian Leehan • 612-673-4583