Is hypnosis a distinct form of consciousness? It isnt that special according to an article in Scientific American Mind. (here). Lilienfeld and Arkowitz also point to a number of false beliefs about hypnosis.
having failed to find reliable markers of trance after 50 years of careful research, most researchers have concluded that this hypothesis [that hypnosis is a unique state of consciousness] has outlived its usefulness. Increasingly, evidence is suggesting that the effects of hypnosis result largely from peoples expectations about what hypnosis entails rather than from the hypnotic state itself.
They list a number of misconceptions: relaxation is not necessary and people have been hypnotized while pedaling vigorously on a stationary bicycle; subjects are awake not asleep; subjects can resist suggestions and are not mindless automatons; posthypnotic amnesia only occurs when subjects expect it; literalism is not displayed to any higher degree than in people simulating hypnosis; trance logic is also a function of peoples expectations; the increased theta band activity is probably due to quiet concentration; increased anterior cingulated cortex activity is present whenever contradictions are perceived; suggestibility is only increase by something like 10%.
Perhaps the only thing that is happening is that when we guess as to the reasons for our actions, we make a different sort of guess when we think we are in a hyponotic trance then we would make normally.