Hypnosis and the senses
An exercise which is sometimes done with hypnosis is the modification of someone's senses. More precisely, they are given a suggestion---post-hypnotic or during the trance---that something they are about to experience is different than what it really is. For example, someone can be given an onion to eat and be told that it's a piece of fruit. This can be fun and is generally harmless as long as the suggestion is cancelled appropriately once the exercise is done.
While sometimes done for fun, these exercises can also be useful indicators of how deeply hypnotised someone is. Some real sensations can be very strong and consequently difficult to hypnotically overcome. When they are overcome and the subject experiences what they're told rather than what's really happening this can be an excellent sign of a deep trance.
Below is a brief exploration of some more-or-less common scenarios involving the manipulation of the senses via hypnosis.
As mentioned above, an interesting sense to manipulate is taste. This can also sometimes be funny to watch. Suggesting to someone that what they are to eat is a piece of fruit when it's actually an onion can be good as a test of depth of trance . This can become funny when you arrange to cancel the suggestion mid-mouthful.
You can also go the other way and suggest that some food which they normally really like has suddenly become the most foul-tasting thing they have every had in their mouth.
One of the classic tests of depth of trance used to be waving a small cup of cloudy ammonia underneath a subject's nose after suggesting to them that they either couldn't smell anything (also known as anosmia), or that they were about to smell some lovely perfume.
Cloudy ammonia is a cleaning agent. Not quite so common these days, it used to be found in most laundries or under most kitchen sinks. Because cloudy ammonia is extremely strong and usually causes an intense reaction when breathed in through the nose, many hypnotists treated it as an unfakeable indicator that their subject was deeply hypnotised if they didn't react to to it.
Going the other way, of course, you can suggest to someone that something which has no smell at all has either a wonderful scent or a really bad scent. For fun---and making sure that you eventually cancel the suggestion---telling someone that their partner has bad body odour can be entertaining.
Hypnotically altering someone's experience of touch can include:
- Temperature - telling someone that something is really hot when it's actually not hot at all, or telling them that something is really cold when it's not. This sort of hypnotic alteration is actually very easy because the body's ability to discriminate temperatures and physical sensations is often quite poor. That said, it has been demonstrated that some subjects can actually get blisters when touched with something they're told is very hot, even when it's not.
- Caresses and rubbing - a particular nice way of changing someone's experience hypnotically can be used in the bedroom. Telling someone that what they experience when their partner touches them intimately will be more intense than usual can increase their sensitivity, sexual responsiveness and pleasure. Going the other way and telling them that they'll be less responsive can be useful for those who go off prematurely.
- Weight - sometimes in hypnosis shows the subjects may be told that something very light---such as a balloon---is actually very heavy. This can be comical as the subject who can see what they're trying to list is actually a balloon finds that it unexplainably extremely heavy and that they can't shift it. With very muscular male subjects this can sometimes be quite funny. This can be inverted and a subject can be told that something heavy is actually light. They might even be told they have to struggle to stop it floating away (even though it might be chair which is clearly not going to float anywhere).
Manipulation of what someone sees is a common trick in hypnosis shows. In particular, many stage shows include the subjects being told that everyone in the audience is naked. While it's clear that they're not, what the subject experiences is that everyone is, in fact, without their clothes. Many subjects in such situations will make it obvious that they're enjoying the view, while some subjects may feel uncomfortable with all those naked people looking at them.
Selective deafness is sometimes used during hypnosis shows. While deafness doesn't create the sorts of funny reactions which stage hypnotists like to have from their subjects, it can be a fine trick during a home hypnosis demonstration when the subject is told that they can't hear their partner but can hear everyone else perfectly fine.
Remember to cancel this one before the couple goes home.