Very good thoughts. I have a current close friend - of sorts, again a rather autistic relationship - who does what you describe, and yes, she does it when, I think, she's decided the conversation has been not paying enough attention to her for too long - it's very strange and you've pegged that way the actual anger created doesn't seem to be the point, nor the actual substance. She did it on Sat in fact,quite suddenly after a perfectly enjoyable evening , and I, who had a lot on my plate at the time, rather radically did not respond but simply walked away and hid in the toilet for a bit. When I came back we resumed pleasantries and later, very unusually, she rang to apoogise for the lapse(though not quite in so many words :-) . I wonder if that's what to do: like dogs, train them by denying attention rather than giving it..