The term "hypnosis" is derived from the Greek word hypnos, meaning "sleep." Hypnotherapists typically use exercises that bring about deep relaxation and an altered state of consciousness, also known as a trance. Many people routinely experience a trance-like state while they are watching television or sitting at a red light. A person in a trance or deeply focused state is unusually responsive to an idea or image, but this does not mean that a hypnotist can control the person's mind and free will. On the contrary, hypnosis can actually teach people how to master their own states of awareness. By doing so they can affect their own bodily functions and psychological responses.

Throughout history, trance states have been used by shamans and ancient peoples in ritualistic activities. But hypnosis as we know it today was first associated with the work of an Austrian physician named Franz Anton Mesmer. In the 1700s, Mesmer used magnets and other hypnotic techniques (hence the word, mesmerized) to treat people, and while he achieved a number of dramatic "cures" for blindness, paralysis, headache, and joint pain, the medical community was not convinced. Mesmer was accused of fraud, and his techniques were called unscientific.

Hypnotherapy regained popularity in the mid-1900s due to the notoriety and career of Milton H. Erickson (1901 - 1980), a successful psychiatrist who used hypnosis in his practice. In 1958, both the American Medical Association and the American Psychological Association recognized the therapy as a valid medical procedure. Since 1995, the National Institutes of Health (NIH) has recommended hypnotherapy as a treatment for chronic pain.

Other conditions for which hypnotherapy is frequently used include anxiety and addiction.

When something new happens to us, we remember it and learn a particular behavior in response to that circumstance. Memories stored in our brains hold the original physical and emotional reactions that occurred when the given memory was first formed. Each time similar events occur again, the physical and emotional reactions attached to the memory are repeated. These reactions may be inappropriate or unhealthy. In some forms of hypnotherapy, the trained therapist guides you to remember the event that led to the first reaction, separate the memory from the learned behavior, and reconstruct the event with new, healthier associations.

During hypnosis, a person's body relaxes while their thoughts become more focused and attentive. Like other relaxation techniques, hypnosis decreases blood pressure and heart rate, and alters certain types of brain wave activity. In this relaxed state, a person will feel very at ease physically yet fully awake mentally. In this state of deep concentration people are highly responsive to suggestion. If you are trying to quit smoking, for example, a therapist's suggestion may successfully convince you that in the future you will have a strong dislike for the taste of cigarettes.

There are several stages of hypnosis. The process begins with reframing the problem; becoming relaxed, then absorbed (deeply engaged in the words or images presented by a hypnotherapist); dissociating (letting go of critical thoughts); responding (complying whole-heartedly to a hypnotherapist's suggestions); returning to usual awareness; and reflecting on the experience.

During your first visit to a hypnotherapist, you will be asked about your medical history and what brought you to see them -- in other words, what condition it is that you would like to clear up. The specialist will then, likely, explain to you what hypnosis is and how it works. You will then be directed through relaxation techniques with a series of mental images and suggestions intended to change behaviors and alleviate symptoms. For example, people who suffer from panic attacks may be given the suggestion that, in the future, they will be able to relax at will. The hypnotherapist may teach you the basics of self-hypnosis or give you an audio recording for home use. This enables you to recreate the feelings you experienced during the session and reinforce the learning on your own.

Each session lasts about an hour, and most people begin to improve within 4 - 10 sessions. Together, you and your hypnotherapist will monitor and evaluate your progress over time. Children (aged 9 - 12), because they are easily hypnotized, tend to respond after only one or two visits.

Hypnosis is used in a variety of settings -- from emergency rooms to dental offices to outpatient clinics -- to relieve conditions with an emotional or psychological component. Clinical studies suggest that hypnosis may improve immune function, increase relaxation, decrease stress, and ease feelings of anxiety.

Hypnotherapy is effective in reducing the fear and anxiety that accompany pain and uncomfortable medical or dental procedures. For example, when used during an operation, hypnosis may improve recovery time and decrease anxiety as well as pain following the surgery. Clinical trials on burn patients suggest that hypnosis decreases pain (enough to replace pain medication) and speeds healing. Generally, clinical studies indicate that using hypnosis can lessen your need for medication, improve your mental and physical condition before an operation, and reduce the time it takes to recover. Dentists also use hypnotherapy to control gagging and bleeding.

A hypnotherapist can teach you self-regulation skills. For instance, someone with arthritis may be told that they can turn down pain like the volume on a radio.

Hypnotherapy can also be an effective tool for managing chronic illness. Self-hypnosis can enhance a sense of control, which is often eroded by chronic illness.

Children may benefit the most from hypnosis, probably because they are most easily hypnotized.

Clinical studies on children in emergency treatment centers show that hypnotherapy reduces fear, anxiety, and discomfort and improves self-control and cooperation with medical personnel.

Hypnosis is generally safe because it evokes the natural healing state in the body, one of deep relaxation.  However, when considering hypnotherapy for a problem with a medical origin, you must first obtain a proper diagnosis and referral from a physician to understand what is being treated. Sometimes, a referral from a mental health practitioner is necessary for problems of a psychological nature.  Problems exist on many levels - physical, mental, emotional and spiritual - therefore it is necessary to ensure that all levels are being attended to in due course  (although not necessarily at the same time) and this may necessitate a range of practitioners.

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