Maybe it’s because criteria for diagnosis changed about 10 years ago. Maybe doctors are finding kids that had never been diagnosed before. Maybe kids are being shifted from one disability category to another. Maybe it’s a fad diagnosis.

Maybe.

New numbers from Maine’s annual count of special education students show more autistic children here for the 12th year in a row, which is as long as the state’s kept track. In a decade, the figure has grown 754 percent, from 99 students to 846.

“No one appears to have an explanation that’s sound,” said David Stockford, director of special services at the Maine Department of Education.

The Autism Society of America puts the prevalence of autism at about 1 in every 250 people. As far as Stockford can tell, Maine’s rate is about on target with that.

Autism is a neurological disorder, affecting social skills and communication, according to the ASA. It’s four times more common in boys.

Classic symptoms are a delay in spoken language, not talking at all or repeating the same things. There can be rigid adherence to a certain routine, hand and finger flapping or preoccupation with one particular subject.

After a May report found the number of children receiving services for the most severe type of autism in California doubled from 1999 to 2002, ASA President Lee Grossman said in a prepared statement “this study confirms ASA’s stated position that the growth of autism in children is accelerating.”

“Several years ago, the ASA provided the federal government data it believed demonstrated the growing prevalence of autism to be a national health crisis, a crisis our health and human services system is not prepared to meet,” Grossman said.

Fifty years ago, a prominent psychologist theorized autism was caused by “refrigerator mothers.” Women who were too cold, too isolated. They weren’t doing things right. His theory was debunked, but “it’s still out there in some people’s minds,” said Carol Thomas, Emile’s mom.

There is ongoing research into the leading theories that autism could be caused by genetics, some environmental trigger or be linked to a childhood vaccine.

Maine’s part of that research.

It’s one of four states — with Iowa, Michigan and New Mexico — involved with a pilot project that encourages autistic people and their families to donate brain tissue samples at death for study.

“There are all of these theories out there, but we really don’t know what’s causing it, that’s why it’s so important the researchers have brain tissue to work on,” said Donald Brann, executive director of the Autism Society of Maine in Winthrop.

He said the state was picked because his organization has an autism database going back 20 years, along with a paid staff. A lot of states don’t have that.

The oldest person in the database is 67, the youngest 18 months.

When children and adults are diagnosed with autism in Maine they typically contact the society, Brann said, which leaves literature in lots of doctors’ offices.

There are support groups throughout Maine, he said, and occupational and speech therapists who specialize in autism to be referred to. “They’re very busy,” Brann added.

He doesn’t believe the rise of autism is Maine has reached the crisis point, and Dora Ann Mills, the state’s health director, hasn’t flagged it as a particular health issue for Maine.

“The state is being very responsive, more so than other states,” Brann said. State funding for his group, originally cut 20 percent amidst the budget crisis, eventually was restored.

He’s been meeting with a statewide task force of school and health professionals monthly since November.

“We’re trying to get a grasp on what we can do to improve the system,” he said. “I think a lot of schools are overwhelmed.”

Classroom services are certainly better, Brann added, than when his own 30-year-old son was a boy.

The state will put together a commission this summer to look at national research and talk to experts on how to reduce the occurrence of developmental disabilities, spurred by a bill this session by Rep. Arthur Lerman, D-Augusta.

Lerman is the executive director of Support Solutions, which offers services to children and adults.

“We would love to put ourselves out of business. Unfortunately, these days the trend is in the other direction,” said Lerman, who has an office in Lewiston.

He wants to look at the effectiveness of early intervention, whether there is information out there the state ought to be aware of that could reduce the instances of disorders like autism in the next generation. A report is due this winter.