I'm reading Why I Jump, by Naoki Higashida. Higashida has autism and was thirteen when he wrote the book. The first part of the book is written in question and answer format. Question # 14 is "Why do you ignore us when we are talking to you?"
His answer is that he has trouble telling when people are talking to him. He makes an analogy to vision--if you are looking at a mountain in the distance you don't see the dandelion at your feet, and vice versa. He says that for him voices are like that.
Then he makes a recommendation/request. "Use our names first to get our attention, before you start speaking to us."
This struck a chord for me. I try very hard to do this with Middle. Especially when I'm asking him to do something, and most especially when I'm teaching him something new.
I say his name. Then I wait for him to look at me before I say anything else.