How is hypnosis defined? Definitions of hypnosis and suggestion

Hypnosis has often been carved into two separate elements - 'Trance' and Suggestion (e.g. see Heap 1996). This distinction has led to some useful research, and is particularly important when considering the results of neuroimaging research. However, it is important to note that not all researchers agree with this definition (see Barnier 2008).

Figure: Separation of hypnotic 'trance' and suggestion can be a useful way of thinking about the effects of hypnosis

Hypnotic 'Trance'

A hypnotic 'trance' can be brought about by giving a willing participant instructions to focus on the hypnotist's voice, to concentrate their attention, and to pay attention to their inner mental world. Some hypnotic inductions include suggestions for relaxation, but this is not strictly necessary. Researchers debate whether a hypnotic trance is an altered state of consciousness, that is, whether an individual's consciousness is altered by becoming hypnotised (see the state/non-state section for more information on this). We might say someone is in hypnosis if they have:

1. Focused attention
2. Are not attending to extraneous stimuli
3. Are absorbed in some activity, image, thought or feeling

Many hypnotists liken the hypnotic 'state' to everyday experiences which people enter spontaneously, such as:

• Being 'lost in thought' or day dreaming
• Absorption in sport, reading, listening to music etc
• Driving for long distances and not recalling the route taken
• Being absorbed in meditation / relaxation procedures.

A hypnotic induction is where participants are given a series of instructions which, if they follow them, are intended to assist them in achieving a trance state. Hypnotic procedures are intended to encourage focussed attention, disattention to surroundings, and absorption in innter mental world. With practice, some people are able to enter the desired state very quickly: either spontaneously or by thinking through a hypnotic procedure. Hypnotic procedures are generally facilitated by:

1. Encouraging the participant to be non-analytical in their thinking
2. Increasing the participant's motivation and willingness to actively involve themselves with the procedures
3. Raising participant's expectancies of a positive outcome

Suggestion

Hypnotists frequently give suggestions to influence what a participant is thinking or feeling, and it is widely acknowledged that many of the interesting effects associated with hypnosis are actually brought about by suggestion (e.g. see Kihlstrom [2008]). Suggestions differ from everyday kinds of instructions in that a 'successful' response is experienced by the subject as having a quality of involuntariness or effortlessness: it feels as though it is happening by itself. One widely held belief is that being in a 'hypnotic state' facilitates responsiveness to suggestion, and there is some evidence to support this. However, while this might be the case people can also respond to suggestions without being taken through a hypnotic procedure first - in the absence of hypnosis people are said to be responding to imaginative suggestions.

Suggestions are often accompanied by appropriate imagery but the following effects can be produced by direct suggestion without imagery:

• Relaxation (e.g. "You are becoming more and more relaxed as time goes by")
• Arm levitation (e.g. "You might begin to notice your arm becoming lighter, and beginning to float up in the air")
• Analgesia (e.g. "Notice the feeling in your hand becoming less and less, your hand becoming numb")
• Amnesia (e.g. "When you wake up, you won't remember anything that happened during this session")
• Post-hypnotic suggestion (e.g. "Later, when I click my fingers, you will scratch your nose")

Involuntariness: the classic suggestion effect

Whether or not you believe that hypnosis is an altered state of consciousness, the key characteristic of hypnotic responding is involuntariness. This has been called the "classic suggestion effect" (Weitzenhoffer, 1980). As a hypnotic suggestion is carried out by a subject, the subjective experience is typically that the behavior is happening all by itself, involuntarily. For example, if the suggestion is that the subject's arm is rigid like a bar of iron, the classic hypnotic experience is that one's arm has really become rigid, on its own: it is not experienced that one is deliberately holding one's arm stiffly.