Scientists hope to make the process less subjective by observing people's movements.
Indiana legislators discussed Wednesday whether the state should place tighter restraints on the use of seclusion rooms for special needs children.
A recent report from the Center for Disease Control says one in 88 children has autism. Doctors say this could be the result of more diagnoses.
Changes to the state's definition of autism could affect millions of children that rely on school funding for special services.
Environmental factors may play more of a role in the risk for causing autism than genetic factors.