Biofeedback is the field of applied psychophysiology, which uses psychological manipulations to control or regulate physiological responses in the body. This technique teaches patients how to control certain involuntary bodily processes, such as heart rate, muscle tension, blood pressure, and skin temperature, to manage their reactions to stress and to achieve other beneficial changes in symptoms or behaviors. The involuntary functions are monitored with electrodes and displayed on a computer monitor; such monitoring provides feedback to patients as they learn to recognize, respond to, and regulate the subtle signals associated with these processes (Sabo and Giorgi 2000).

Biofeedback grew out of self-regulatory traditions, such as yoga and meditation, which have been practiced in Eastern societies for thousands of years. In the 1960s, researchers became fascinated with yoga masters who could use meditation under laboratory conditions to control bodily functions at astounding levels. For example, in one study, Swami Rama, an Indian yogi, stopped his heart from beating for a full 17 seconds, and then restarted it without any apparent adverse effects. Clinicians realized that, with the help of computer-generated feedback, ordinary individuals who were not yogis could also learn to control some physiological processes by manipulating concrete, visual data reflecting moment-to-moment physiological responses (Sabo and Giorgi 2000).

Clinical biofeedback originally used simple electronic devices housed in bulky wooden boxes. With the advent of computer technology in the late 1980s and 1990s, practitioners and researchers have been able to streamline biofeedback instrumentation and collect and analyze more extensive and precise physiologic data. As a result, practitioners have expanded the scope of biofeedback's clinical applications to include a wider variety of medical and psychological conditions and to promote peak athletic and mental performance states (Sabo and Giorgi 2000). Today, biofeedback is mainly used for conditions that may be caused or aggravated by stress, particularly tension and migraine headaches, chronic pain, and hypertension.

Biofeedback teaches patients to use a type of intuitive control known as passive volition to develop greater awareness and regulation of physiologic processes. The mechanism by which voluntary control is exerted is not well understood. However, the attention and arousal levels, which are mediated by the thalamic and reticular activating systems in the brain, seem to play a key role in regulating involuntary bodily functions (Sabo and Giorgi 2000).

Any physiologic response that can be monitored is amenable to intervention via biofeedback techniques. Patients may also use breathing techniques, imagery, and relaxation methods to facilitate control over their physiologic responses. Such methods are not absolutely necessary, however, since the learning process involved seems to be mediated by simple attention to the task. The most common types of biofeedback techniques include electromyography (EMG), which measures muscle tension; thermal biofeedback, which measures skin temperature; and electroencephalography (EEG), which measures brain wave activity (Sabo and Giorgi 2000).

Biofeedback training typically takes place over a series of sessions in the practitioner's office. Electrodes attached to the patient transmit physiological data to a computer, which provides visual and/or auditory feedback that is explained to the patient by the practitioner during training sessions. The practitioner may also teach various relaxation methods and deep breathing techniques, coaching the patient on how and when to use these methods (Sabo and Giorgi 2000). By observing instantaneous changes in muscle tension, temperature, and/or brain waves, the patient gains an understanding of the physiological response(s) involved and learns to effect a change in behavior.

Studies show that various forms of biofeedback are effective for a range of conditions. For example, the results of a randomized, controlled trial suggest that biofeedback shows considerable promise for the treatment of urinary incontinence, which affects over 15 million Americans; biofeedback may thus offer a less invasive and more widely applicable alternative to medication (Resnick 1998). An earlier study indicated that biofeedback, by improving bladder muscle function, reduced the frequency of symptoms in patients with urge incontinence by an average of 94 percent, in patients with detrusor motor instability by 85 percent, and in patients with stress incontinence by 82 percent (Burgio et al. 1985). In view of such studies, the Agency for Health Care Policy and Research has recommended biofeedback therapy as a treatment for urge, stress, and mixed urinary incontinence (AHCPR 1996).

Another study followed the progress of 100 patients with fecal incontinence referred for biofeedback training. Overall, 43 of the 100 patients regarded themselves as cured after treatment, while another 24 improved (Norton and Kamm 1999). Similar results have been reported in the biofeedback treatment of obstructive defecation as well (Rao 1998).

Research also suggests that vasodilation induced by thermal biofeedback decreases the frequency of symptoms in those with Raynaud's disease (Freedman 1991). EMG biofeedback has been shown to reduce pain, morning stiffness, and the number of tender points in patients with fibromyalgia (Leventhal 1999). Furthermore, a review of the current research on chronic insomnia suggests that biofeedback may be an effective technique for diminishing the somatic arousal (e.g., muscle tension) that leads to sleeplessness (Chesson et al. 1999).

In addition, an experimental study of 14 alcoholic outpatients indicates that the combination of temperature biofeedback and alpha-theta EEG neurofeedback may help reduce self-assessed symptoms of depression and sustain sobriety in alcoholics (Saxby and Peniston 1995). Finally, biofeedback can be used effectively for certain ailments in children. A clinical trial indicates that EEG training can improve Tests of Variables of Attention (TOVA) performance, behavioral ratings, and Wechsler intelligence (WISC-R) scores in children with Attention Deficit/Hyperactivity Disorder (Lubar et al. 1995). Thermal biofeedback has also been reported to help alleviate migraine and chronic tension headaches among children and adolescents (Annequin et al. 2000).

Biofeedback is considered a safe procedure; no adverse events are known to have been reported in the literature to date (Sabo and Giorgi 2000).

No contraindications are known to have been reported in the literature to date (Sabo and Giorgi 2000).

In addition to the conclusions in the section entitled Clinical Applications, EEG neurofeedback may be useful for treating anxiety, depression, epilepsy and related seizure disorders, closed head injuries, learning disabilities, posttraumatic stress disorder, certain endocrine disorders, autoimmune disorders, autism, chronic pain, muscle spasms, and multiple chemical sensitivities. Both thermal and EMG biofeedback have been used to treat hypertension, and EMG biofeedback may also be helpful for muscle spasms, back pain, and spinal cord injury (Sabo and Giorgi 2000).

Biofeedback offers great promise as a non-invasive therapy for a wide range of conditions that actively involves the patient as a partner in his or her own care. Future research is needed to validate its efficacy, establish treatment protocols, and expand its applications (Sabo and Giorgi 2000).

There are many training programs throughout the United States; nurses, physicians, and psychologists trained in behavioral medicine often become trained in biofeedback as well. The Biofeedback Certification Institute of America provides an examination and certification for professional practitioners (Sabo and Giorgi 2000). In addition, local chapters of such national organizations as the Association for Applied Psychophysiology and Biofeedback and the Society for Neuronal Regulation can be found in many states.

For information on referrals to qualified practitioners, third-party reimbursement, and annual seminars and conferences, contact the Association for Applied Psychophysiology and Biofeedback in Wheat Ridge, CO at 303-422-8436 or on the Web at www.aapb.org. The Biofeedback Certification Institute of America in Wheat Ridge, CO is affiliated with the AAPB; contact the organization at 303-420-2902 or on the Web at www.bcia.org for referrals and information about the credentialing process for biofeedback training. The Society for Neuronal Regulation in Merino, CO publishes the Journal of Neurotherapy, keeps the biofeedback community informed of current research, and sponsors several training programs for practitioners at its annual conferences. Contact the society at 800-488-3867 or on the Web at www.snr-jnt.org.

AHCPR. Clinical Practice Guideline Number 2: Urinary incontinence in adults: acute and chronic management. Rockville, MD: Agency for Health Care Policy and Research, US Dept of Health and Human Services; 1996. AHCPR publication 96-0682.

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Saxby E, Peniston EG. Alpha-theta brainwave neurofeedback training: an effective treatment for male and female alcoholics with depressive symptoms. J Clin Psychol. 1995;51(5):685-693.