Have you ever wished you could avoid going to the doctor by simply willing your symptoms to disappear? With biofeedback, you may be able to do just that, at least to a degree.

Biofeedback is a form of complementary and alternative medicine (CAM) that falls under the category of mind-body therapies. Using feedback from a variety of monitoring procedures and equipment, a biofeedback specialist will try to teach you to control certain involuntary body responses. These responses include:

• Brain activity
• Blood pressure
• Muscle tension
• Heart rate

Once you learn to recognize and control these responses, you can use this mind-body technique to help treat a wide range of mental and physical health problems, from preventing a panic attack to taming a migraine or curing incontinence. Even if you don't have a specific disease or condition, biofeedback may help you improve your overall health and sense of well-being.

Biofeedback has been shown helpful in treating about 150 medical conditions, including:

• Asthma
• Reynaud's disease
• Irritable bowel syndrome
• Hot flashes
• Nausea and vomiting associated with chemotherapy
• Incontinence
• Headaches
• Irregular heartbeats (cardiac arrhythmias)
• High blood pressure
• Epilepsy

Clinical trials sponsored by the National Institutes of Health are currently investigating the role of biofeedback in treating essential hypertension — high blood pressure of unknown cause.

You can receive biofeedback training in physical therapy clinics, medical centers and hospitals. A typical biofeedback session lasts 30 to 60 minutes.

During a biofeedback session, a therapist will apply electrical sensors to different parts of your body. These sensors will monitor your body's physiologic responses to stress — for instance, your muscle contraction during a tension headache — and then feed the information back to you via auditory and visual cues. These cues may take the form of a beeping sound or a flashing light. With this feedback, you'll start to associate your body's response — in this case, pain — with certain physical functions, such as your muscles tensing.

Once you begin to recognize that your headache, in this case, is the result of tense muscles, the next step is to learn how to invoke positive physical changes in your body, such as relaxing those specific muscles, when your body is physically or mentally stressed. Your eventual goal will be to produce these responses on your own, outside the therapist's office and without the help of technology.

Your therapist may use several different techniques to gather information about your body's responses. Determining the one that's right for you will depend on your particular health problems and objectives. Machines and techniques include:

• Electromyogram (EMG). An EMG uses electrodes or other types of sensors to measure muscle tension. By alerting you to muscle tension, you can learn to recognize the feeling early on and try to control the tension right away. EMG is mainly used to promote the relaxation of those muscles involved in backaches, headaches, neck pain and grinding your teeth (bruxism). An EMG may be used to treat some illnesses whose symptoms tend to worsen under stress, such as asthma and ulcers.

• Temperature biofeedback. Sensors attached to your fingers or feet measure your skin temperature. Because your temperature often drops when you're under stress, a low reading can prompt you to begin relaxation techniques. Temperature biofeedback can help treat certain circulatory disorders, such as Reynaud's disease, or reduce the frequency of migraines.
  
• Galvanic skin response training. Sensors measure the activity of your sweat glands and the amount of perspiration on your skin, alerting you to anxiety. This information can be useful in treating emotional disorders such as phobias, anxiety and stuttering.

• Electroencephalogram (EEG). An EEG monitors the activity of brain waves linked to different mental states, such as wakefulness, relaxation, calmness, light sleep and deep sleep.

Once you decide to try biofeedback, you'll need to find a qualified biofeedback therapist. Contact the Biofeedback Certification Institute of America (BCIA) and ask for the names of people certified in your area. More than 2,000 BCIA-certified professionals practice in the United States. BCIA therapists must be licensed in another area of health care or be working under the guidance of a health care professional. They should be accustomed to dealing with patients, and you can expect them to have a good bedside manner.

If you can't find a BCIA-certified therapist in your area, ask your doctor or another medical expert with knowledge of CAM to recommend someone who has experience in treating the specific symptoms that are bothering you. As with any health care practitioner, you may have to meet with several individuals to find the one with whom you feel most comfortable.

Be sure to ask each therapist to provide references. Find out the therapist's other areas of professional expertise, and whether he or she has experience treating the specific problem for which you're seeking help. Check to see whether your health insurer will cover the cost of treatment.

Biofeedback may appeal to you for several reasons:

• It can reduce, or even eliminate, your need for medication.
• It has the potential to help conditions that have not responded to medication.
• It helps puts you in charge of your own healing by providing measurable feedback, allowing you to monitor your progress and learning.
• It can decrease your medical costs.

On the other hand, you may be hesitant to try biofeedback because experts aren't entirely sure how the therapy works. Many people who have tried biofeedback can't explain how they're able to control their bodies to relieve their symptoms.

To truly assess whether biofeedback is effective in treating your particular symptoms, keep a daily diary to monitor your use of the treatment as well as how you feel before, during and after the therapy.

Although biofeedback is considered safe, talk to a doctor knowledgeable about this form of CAM if you suffer from depression, severe psychosis, or diabetes or other endocrine disorders. Biofeedback can interfere with the use of some medications, such as insulin.