I fully endorse the comments about dementia. A few months ago I had a request to use hypnosis to try to alleviate distressing tinnitus in an elderly woman. The referring physician asked if I would make a housecall as she was too frail to travel. He also mentioned that she was "A bit deaf and a bit confused at times." She was taking a considerable quantty of medication for hypertension and heart failure. I arrived at her home one evening and produced a tape recorder to record our work. She did not know what the machine was for! She did not know if she and her husband had a tape machine that they could use to play back the tape! She knew that I was a doctor but did not know why I had come despite my telephone call of the prevuious day to her! She had already gone to bed for the evening. At this point I realised that the chances of making a great difference using hypnosis were close to zero. Given that I was there I decided to proceed as I was intruiged to discover what would happen. Her deafness and tinnitus made it hard for her to hear my pre-induction discussion and she she did not seem to have much understanding. When I asked her to close her eyes she found that her hearing diminished still further. Presumably she had been lip reading for years without appreciating this. At this point I began to wonder where the Candid Camera team had their camera. I decided that since I could do no harm I then spent the next 30 minutes weaving a wonderfully multilayered metaphorical range of stories about tinnitus. Technically the words were excellent. It would perhaps have been wonderful had she not had to get out of bed 3 times in the 30 minutes to go to the toilet! I broke many of the rules I teach and it was a valuable lesson in appreciating the limitations of hypnosis and treating each case on its own merits.