I am writing about my 5 year old grandson. He has been to one doctor who has said he may have an autism spectrum disorder. I ve read a little bit about autism and I don t really sign of that. I m noticing something however. Sometimes when he is quietly sitting coloring or eating, he stops and his neck and both arms go into a pattern of a cycle of shaking and moving. He doesn t seem aware that he is doing this. It lasts for about a minute or two. And then he resumes his activity.