What is a "posthypnotic suggestion"?

What is a "posthypnotic suggestion"?

John McGrail, C.Ht. (Certified Clinical Hypnotherapist) gives expert video advice on: What happens during a typical hypnosis session?; What can I expect while I discuss my hypnosis goals with a hypnotherapist?; What is happening to me when I am in a hypnotic trance? and more...

A posthypnotic suggestion is a suggestion that is given to a client while they are in hypnosis to help effect a change after they come out of hypnosis. For instance, I might say something like, "The harder you try to find that fear of public speaking, the harder that it becomes." In fact, you find that you cannot find that fear anymore. You are unable to find that fear. Instead, it's replaced by a feeling of deep calm, centeredness, and peace of mind. If I give that posthypnotic suggestion properly and in the right context, then later on, when the person's standing up in front of the crowd, their mind will remember, "Oh yes, deep calm. I'm not afraid." With reinforcement, that becomes the new behaviour.