I have a kiddo who begins to yawn whenever we do oral placement exercises. The longer we do them, the more he yawns and longer duration they are. It doesn't take much work before he begins to yawn. If we take a break and begin again, he starts to yawn as soon as tools are presented. He presents with hyposensitivity and is very much an oral sensory seeker. Any idea what would be causing him to yawn?