Evidence is growing for a notion long observed by doctors and parents: Some children with autism appear to grow out of their symptoms and recover fully.

The reasons aren't entirely clear, but a recent study adds to the body of scientific work suggesting some autistic people get better. Led by a team from the University of Connecticut, researchers last week reported that they had identified 34 people who had all been diagnosed with autism by age 5 but years later were indistinguishable from peers on language, socialization...