IRVINE, Calif. — They might have trouble recognizing their children or remembering their address, but they sang "Amazing Grace" and recited the Lord's Prayer from memory.

More than 30 seniors with Alzheimer's disease and other dementia-related conditions attended Mass at St. John Neumann Roman Catholic Church, where familiar religious rituals awakened their long-term memories.

"It's seeing the stained-glass windows. It's sitting in the pew and seeing the minister," said Jacque Schweppe, an Alzheimer's Association volunteer. "It's a blessing to see how many respond. We know for most of them as soon as they leave those doors it's going to be lost for them."

Worshippers leaned their walkers against the brick walls of the church and shuffled slowly into the first five pews.

Bus drivers and caretakers from assisted-living facilities helped some of their charges kneel, stand and sit as needed during the service.

Rows of white-haired men and women stared straight ahead at a mural of Jesus Christ. And from the first notes of "Amazing Grace," strong voices from every pew could be heard.

The brain disorder typically attacks short-term memory first and gradually erodes patients' judgment and ability to take care of themselves.

Some chapters of the Alzheimer's Association sponsor monthly worship services that are specialized for the patients. Churches and temples host the weekday services and lunch on a rotating basis at no cost.

Priests, ministers and rabbis are instructed to keep their sermons short, incorporate traditional hymns and Scriptures and avoid mention of Alzheimer's.

"I can tell by the look on some of the faces, they were inspired," said Lee Nick, a driver at Brighton Gardens in Yorba Linda, Calif. "They really came alive."

Vans from four Alzheimer's housing facilities brought the patients to the church. Viola Vighi, 99, said she was thrilled to be able to go to church again.

"I thought we were just going for a ride," Vighi said. "I'm used to going to church on Sundays but I don't get the chance to do it now."

Assisted-living facilities often host religious leaders in their recreation rooms for worship services. But actually visiting the houses of worship seems to encourage the patients to participate in the service, volunteers said.

Even those who don't practice the particular religion can gain something.

"We've gotten a good idea of what the other services are like and I appreciate that," said Mary Margaret Brown, who is "not 100 but not that far off."

Returning to a familiar childhood compass point such as a church can be calming and reassuring for patients with Alzheimer's, who often suffer from anxiety.

"Alzheimer's is a disease that disconnects people," said Cordula Dick-Muehlke, a psychologist and executive director at Adult Day Services of Orange County. "Even though Alzheimer's might take away one's cognitive ability and change their personality, beyond that there's a spiritual element, and these rituals and music are a way of connecting with that."

With sometimes shaky hands, the worshippers held their hymnals and sang along to "How Great Thou Art."

The Rev. John Shetler carried Communion to those who wanted to stay in their pews. At this service, it's acceptable to talk, cry out or nod off.

"We're all sick in some way, but the lord Jesus Christ is our healer," Shetler told the congregation. "If we fall asleep while we're saying our prayers, He finishes them for us, I bet."