WHEN DOES AUTISM START?

And its current treatment is all over the map. Every day, it seems, there's a new "cure." With no known cause and no clear guidance, parents must navigate a maze of costly therapies, most of which have little hard-core science to prove their effectiveness. Many children now take medications, ranging from anticonvulsants (about one third suffer from seizures) to stimulants like Ritalin to calm hyperactivity. Low doses of antidepressants such as Prozac may help reduce the severity of repetitive behaviors. And risperidone, an anti-psychotic drug, can quell aggression and tantrums, says Dr. Christopher McDougle, of the Indiana University School of Medicine. The drug, whose side effects include weight gain and sedation, is now before the FDA and could become the first medication approved specifically for autism.

Drugs, however, won't help a child learn to speak. One of the few treatments that just about everyone agrees is critical is behavioral intervention, which uses word repetition, game-playing and specialized exercises to develop a child's language and social skills. At the Lovaas Institute in Los Angeles, senior instructor Sona Gulyan engages Adam Ellis, who turns 4 next month, in language drills known as discrete trials. "Say 'hi'," says Gulyan. Adam, a chubby-cheeked little boy in jeans and a white T shirt, responds with a "k" sound. "No, 'hi'," says Gulyan. After several failed attempts, Gulyan switches the focus. "Do this," she says, pointing to her nose. Adam imitates the gesture and is congratulated. And then it's back to the original task: "Say 'hi'." Finally, success--and an orange balloon as a reward. In 1987, founder Ivar Lovaas reported that children who received an average of 40 hours a week of his intensive one-on-one therapy called Applied Behavior Analysis increased their IQs by 30 points, compared with a control group. Other studies, however, have been mixed, and critics believe the program is too militaristic. But for Adam's mother, Megan, it's progress that matters. "He has mastered so many skills," she says. "It's just amazing."

Things are more relaxed at Cleveland's Achievement Centers for Children, where Lisa and Tim Brogan play with their son, Alex. Alex is learning to communicate through an intervention called Floortime, which focuses on a child's individual strengths and his relationships with others. Kids learn to engage with their parents through "circles of communication." If Alex wants to line up toy cars in a row, his dad will join him, then nudge one out of place. The move prompts Alex to interact with his father--a circle of communication--rather than isolate himself with the toys. "We have come such a very long way," says Lisa.

Children with autism have as many styles and personalities as any group of toddlers. A behavioral intervention that suits one child (or his parent) won't necessarily work for another. Many treatment centers now mix techniques from different approaches, including one of the newest on the block: Relationship Development Intervention, or RDI. Here, parents learn how to use everyday events as teachable moments. A trip to the grocery store, for example, becomes an opportunity for kids to learn to adapt to sensory overload--the chatter of shoppers, 100 different kinds of cereal. In the past, Pam Carroll's son, Morgan, now 9, was fixated on instant oatmeal with blueberries, and he melted down if it wasn't available. Now he roams the aisles in Gainesville, Fla., and helps his mom shop. Linda Andron-Ostrow, a clinical social worker in Los Angeles, likes the way RDI empowers parents and allows for creative thinking. "Life isn't structured," she says.

With autism's medley of symptoms--which can include a heightened sensitivity to sound and picky eating habits--many families search for alternative treatments. Kacy Dolce and her husband, Christopher, recently took their son, Hank, 4, to see Mary Ann Block, an osteopath in Hurst, Texas, for a $2,500 assessment. Block prescribes vitamins and minerals, diets free of wheat and dairy, and a controversial treatment, chelation, which strips the body of metals like mercury. Block believes these toxins could come from vaccines and are at the core of autism. Mainstream doctors, pointing to scientific studies showing no connection, worry that chelation puts children at serious risk. Despite the possibility of dangerous side effects, like liver and kidney problems, the Dolces say they'd consider it. "We don't know enough yet to say no," says Kacy. "I'll do anything to help our child."

What parents really need is a road map. Earlier this month six U.S. medical centers joined forces to launch the Autism Treatment Network, which will evaluate therapies, pool data and, ultimately, create guidelines. "We can't have parents chasing down the latest treatment," says Peter Bell of Cure Autism Now, a research and advocacy group allied with the effort. "We need to understand what works." At the forefront of ATN is Massachusetts General's Ladders program, where Dr. Margaret Bauman is using a multidisciplinary approach. In addition to offering standard regimens like physical therapy and behavioral intervention, Bauman assesses overall health. When she saw a teenager crying and twisting her body, symptoms other doctors attributed to autism, Bauman sent her to a gastroenterologist, who found ulcers in her esophagus. The writhing was caused by pain. A boy's head-banging went away after he was treated for colitis. "We really have to start thinking out of the box," says Bauman.