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You Are Getting Sleepy: The Pros and Cons of Hypnosis

leigh urbschat's picture

When most of us think about hypnotism or hypnotists we might think back to a high school assembly or carnival show in which we’ve watched volunteers get up on stage and made to act like chickens. For most people, the idea of hypnotism may be more of a magic show than means for psychotherapy or forensic investigation. These two fields, however, have been relying recently on hypnotism to get answers. Therapists may use hypnotism to uncover childhood abuse that can lead to other problems in adult patients, or to rid a patient of a phobia or bad habit. Hypnotism has also been used by the judicial system to enhance the memories of witnesses or victims of crimes. In both fields, however, the use of hypnotism to get to the bottom of things is a controversial subject. Hypnotism can often lead to pseudomemories in the hypnotized subject, which can be very misleading or simply false. With the information that follows, I hope to make readers familiar with the risks of using hypnotism both inside and outside the therapeutic context as well as with when hypnotism can be of real psychological help.

To understand the pros and cons of hypnotism, it is first helpful to know how hypnotism works. Hypnotism is a trance-like state, in which the suggestibility of the subject increases immensely. The relaxation and imagination of the subject are also heightened, making the condition seem almost like sleep, although the subject is awake and fully conscious. Most of us experience some form of self-hypnosis everyday, in which we tune out most of the stimuli around us to focus on a certain task while remaining fully conscious.(1) Just think of the trance-like state you enter while reading, watching a movie, or daydreaming. When a hypnotist hypnotizes a subject, however, it is most often with specific relaxation and focusing exercises. The most widely accepted explanation of what happens within the brain when one becomes hypnotized involves the subconscious mind. When we go about our daily lives we are only aware of the thought processes within our conscious minds. The subconscious, however, is always there sorting through the ideas and information that is stored there and also controlling our automatic processes, such as breathing. It is believed that the exercises used by hypnotists subdue the conscious mind, as with sleep, so that it has a less active roll in one’s thinking and the unconscious mind can take over. In short, it is widely believed that when hypnotized, the hypnotist is working openly with the subject’s unconscious mind.(1)

Supporting this theory is data that shows that while hypnotized, subjects experience increased lower frequency brain waves and decreased high frequency brain waves. The lower frequency waves are those associated with sleep and dreaming, while the high frequency waves are associated with being awake. This fits the theory, as it is during sleep when the conscious mind is also subdued. Studies of the cerebral cortex have also shown that while hypnotized, subjects show increased activity in the right hemisphere and decreased activity in the left. A decrease in activity in the left hemisphere signifies a decrease in logical thinking, which supports the theory that the conscious mind has been subdued during hypnosis.(1)

Hypnosis is a treatment most often used by psychiatrists to help patients over come a phobia or bad habit. Both conditions are embedded in the subconscious of a subject. Once hypnotized the hypnotist is able to work within the subconscious of the subject to try and reverse the condition by, for example, associating a negative feeling with a certain habit.(1) Hypnotism is also used by psychiatrists to enhance the memory of patients. This more controversial practice may be used if a doctor believes a patient to have experienced some kind of suppressed childhood abuse that is resulting in the adult patient’s problems later in life. The goal of the psychiatrist is to excavate any repressed memories so that they can be dealt with and the patient’s related condition can be treated.(2) The problem with this process, however, is that when a hypnotized person receives the prompt to think back to a time in childhood in which they were abused, they often create pseudomemories where they believe that the suggestion is a real memory. When the patient awakes they are often convinced that the memory is vividly real. In Jean-Roch Laurence and Campbell Perry’s study on pseudomemories, they found that almost half of highly hypnotizable subjects created pseudomemories when given a suggestion (such as that they heard a loud noise the night before during sleep) by the hypnotist during hypnosis.(3) Even after they were told by the hypnotist that the memory had only been a suggestion, the subjects still believed that the memory was real.(3) Studies done by Martin T. Orne, et al. also revealed that although, while hypnotized, a subject’s ability to recall images increases, the number of incorrect answers given also increases. Jane Dywan and Kenneth Bowers study on the same subject found that hypnotized subjects recalled twice as many images as the control subjects, but with three times as many errors.(4) It appears that the probability of correctly recalling information is directly related to the number of items a subject is willing to list as memories, possibly resulting from the subject being less cautious (due to the subdued conscious mind) rather than having increased sensitivity to memory traces.(4)

The creation of pseudomemories can be extremely problematic when it comes to using hypnosis within a forensic investigation. Hypnosis may be used to try and enhance the memory of a witness or victim of a crime. It is very important that the hypnotist does not ask leading questions, however, as any suggestion can result in pseudomemories. Often in stressful situations, such as the court room, these pseudomemories can become extremely vivid in the witness’s mind. It is also important to recognize that when a hypnotist asks a witness to go through the events of a crime they are almost always asking them to fantasize. They may ask the witness to “slow down” or “zoom into” certain scenes in their mind. Obviously, the subject’s retina in the original situation was unable to do these things, creating a sense of fantasy to begin with.(3) Witnesses who were originally unsure of the situation can become certain of incorrect events as well. As said previously, subjects who experience pseudomemories often strongly believe them to be true. This can be very dangerous if a witness believes an event inadvertently suggested by the hypnotist, which is actually a pseudomemory, is fact. Clearly any evidence derived from hypnosis in forensic investigation should be considered with a great deal of skepticism.

Hypnotism has been helpful for many people in breaking bad habits and overcoming phobias. In recalling memory, however, the problems of hypnosis must be considered as well. The creation of pseudomemories makes the manipulability of our minds frighteningly real. We learned in class about our own ability to shape our minds, but knowing that others can as well changes the picture a great deal. Just knowing that our individual brains can be swayed to a particular side so easily makes them seem a lot less individual.




1. Harris, Tom. “How Hypnosis Works.” Accessed May 14, 2007.

2. Orne, Martin T. et al. “ ‘Memories’ of Anomalous and Traumatic Autobiographical Experiences: Validation and Consolidation of Fantasy Through Hypnosis.” Psychological Inquiry, Vol. 7, No. 2. (1996), pp. 168-172. Accessed May 14, 2007.

3. Laurence, Jean-Roch and Campbell Perry. “Hypnotically Created Memory among Highly Hypnotizable Subjects.” Science, New Series, Vol. 222, No. 4623. (Nov. 4, 1983), pp. 523-524. Accessed May 14, 2007.

4. Dywan, Jane and Kenneth Bowers. “The Use of Hypnosis to Enhance Recall.” Science, New Series, Vol. 222, No. 4620. (Oct. 14, 1983), pp. 184-185. Accessed May 14, 2007.


Anonymous's picture

Can hypnosis help stop bad

Can hypnosis help stop bad thoughts or OCD thoughts from dominating ones mind? A bad thought came to me a while ago and it traumatized me and now the thought comes repeatedly because of my anxious reaction to it.

Orik_Ibad's picture

Yes, hypnosis can

Sure, hypnosis can help you control your negative thoguhts, as hypnosis affects your subconsious mind. You will also be able to gain positive thinking if you use particular hypnosis inductions.

Anonymous's picture

can hypnosishelp to control

can hypnosishelp to control negative thoughts of a person