This is a bit different than what happens with me,in that you seem to go on auto pilot. But I have had situations where I had thought I had made a spoken reply to someone,and when I would ask why they didn't reply,they would answer,Because you didn't say any thing.'' But in all honesty,I had thought I had been speaking because I was thinking so strongly.I haven't a clue as to what this would be called,and have even tried looking this up on line and recieved a no results found message. Perhaps if you know a doctor,you could ask him/her? And when you do this again,it might be good to write the words down as they are thought out,then that way you can keep a log of what words you have thought while on auto pilot,and number of times also. This is the only suggestion I can think of right now.