pavlov

Ivan Pavlov believed that hypnosis was a "partial sleep". He observed that the various degrees of hypnosis did not significantly differ physiologically from the waking state and hypnosis depended on insignificant changes of environmental stimuli. http://www.soulcast.com/Louis_J_Sheehan_Esquire_१ Pavlov also suggested that lower-brain-stem mechanisms were involved in hypnotic conditioning.

Currently a more popular "hyper-suggestibility theory" states that the subject focuses attention by responding to the hypnotist's suggestion. As attention is focused and magnified, the hypnotist's words are gradually accepted without the subject conducting any conscious censorship of what is being said. This is not unlike the athlete listening to the coach's last pieces of advice minutes before an important sport event; concentration filters out all that is unimportant and magnifies what is said about what really matters to the subject.