I just want to write down my understanding about what hypnosis / trance is, please comment if you agree or not, what are your opinions ?
1) there is a sort of critical thinking in the brain that is goal oriented and uses logic and reasoning to filter how a conversation goes and where should be a person's attention, so this critical, goal oriented thinking is governing the imagination of a person
2) Trance is a state where this critical thinking is switched off (or at least its effect on the person's ability to control his/her own thoughts is lessened), where suggestions can induce a dream like state, the person accepts a suggestion as if it was his/her own idea and wants to play around with that idea.
It's a dream like state because in a dream we don't question where our ideas come from, normally we believe everything what we dream, this also explains why authority/trust (as a doctor for example) is related to hypnosis/suggestions, when we are talking to an authority (or someone we trust), we suspend our critical thinking because we know that the other person wants what is best for us or for some other reason ( perhaps authority equals a learned response to a que - the authority - which says that critical thinking must be suspended )
while in trance the person can explore ideas and experiences that would be impossible when not in trance because the person would not let himself/herself to be lead to those experiences - he/she would be too resistant to go there to begin with
3) the third question is what happens after a person comes out of trance ? once the critical thinking is restored