Since the afflicted are healthy and normal in appearance, autism is difficult to detect in early infancy. Most parents of autistic children don't realize there is anything wrong until their children are one or two years old or even two or three.
由於外表看來健康正常，在襁褓期不容易察覺，多半要到孩子一、二歲，甚至二、三歲時，家長才會感覺孩子不太對勁。