In my self-hypnosis scripts for Summon the Warrior: http://SummontheWarrior.com http://SummontheWarrior.com I use sensory recall and a few other techniques that

In my self-hypnosis scripts for Summon the Warrior: http://SummontheWarrior.com http://SummontheWarrior.com I use sensory recall and a few other techniques that can induce hallucinations. Certainly, they can be triggered by a smell or sound. Negative hallucinations are even more common (like not being able to see the car keys when they are right in front you). I see people show signs of negative hallucinations when they walk past litter on scenic paths.