A technique in which various monitoring devices are used to help a person learn to voluntarily alter normally involuntary body functions such as brain activity, blood pressure, muscle tension, or heart rate.
Biofeedback has been shown to be helpful in treating a number of medical conditions, including asthma, Raynaud disease (intermittent episodes of decreased blood flow to the extremities), hot flashes, incontinence, and high blood pressure. It also seems to help people relax and enter a calmer state of mind, enhancing their overall health and well-being.
Biofeedback can be administered in a number of ways. An electromyogram (EMG) uses electrodes or other sensors to measure muscle tension. By showing people when their muscles are tensed, it can help them learn to relax these muscles, possibly alleviating such conditions as backaches, headaches, and neck pain, which are sometimes associated with muscle tension. It can also be helpful for medical conditions that are worsened by stress, such as asthma.
In temperature biofeedback, sensors are attached to the person’s fingers or feet to measure skin temperature. A low skin temperature reading may indicate stress, so such a reading can serve as a prompt to begin relaxation techniques. This type of biofeedback may be useful in easing conditions related to circulation, including migraines and peripheral vascular disease.
In galvanic skin response training, sensors measure the activity of a person’s sweat glands and the amount of perspiration on the skin, both of which are affected by anxiety. This type of biofeedback can be used to treat phobias and anxiety.
An electroencephalogram (EEG) monitors brain waves, which reflect different mental states, including sleep, wakefulness, and relaxation. Biofeedback using EEG may help people develop a calmer, more focused state of mind and may be useful in treating mood swings and conditions such as attention deficit disorder.
There is some evidence that biofeedback can improve blood flow to the feet in people with peripheral arterial disease and/or peripheral neuropathy. This is of particular interest to people with diabetes since the combination of poor circulation and nerve damage related to diabetes can set the stage for wounds that heal slowly or foot ulcers.
A prospective, randomized study reported in the Journal of the American Podiatric Medical Association in March 2001, was designed to determine the effects of biofeedback-assisted relaxation training on the healing of foot ulcers. While the control group received only traditional medical care, the experimental group received standard medical care combined with a biofeedback-assisted relaxation training program designed to increase blood circulation to the feet. In the experimental group, 14 of 16 ulcers (87.5%) healed, while in the control group, only 7 out of 16 (43.8%) healed.
Anyone seeking biofeedback should make sure that his biofeedback therapist is properly certified by contacting the Biofeedback Certification Institute of America. (Log on to www.bcia.org or call  420-2902 for more information.) Also, anyone taking insulin should be aware that by enhancing the body’s use of glucose, biofeedback therapy can lower blood glucose levels for up to four hours after a session. Therefore, it is a good idea to check blood glucose levels frequently following biofeedback.