People with autism, intellectual disabilities or both are three times more likely than the general population to develop Parkinson’s-like symptoms as they age. Plus, a study seems to cast doubt on the theory that sleep cleanses the brain and what to do when funding runs out. People with autism, intellectual disabilities or both are three times more likely than the general population to develop Parkinson’s-like symptoms as they age. Plus, a study seems to cast doubt on the theory that sleep cleanses the brain and what to do when funding runs out.