Biofeedback is a treatment technique in which people are trained to improve their health by using signals from their own bodies. Physical therapists use biofeedback to help stroke victims regain movement in paralyzed muscles. Psychologists use it to help tense and anxious clients learn to relax. Specialists in many different fields use biofeedback to help their patients cope with pain.

Chances are you have used biofeedback yourself. You’ve used it if you have ever taken your temperature or stepped on a scale. The thermometer tells you whether you’re running a fever, the scale whether you’ve gained weight. Both devices “feed back” information about your body’s condition. Armed with this information, you can take steps you’ve learned to improve the condition. When you’re running a fever, you go to bed and drink plenty of fluids. When you’ve gained weight, you resolve to eat less and sometimes you do.

Clinicians reply on complicated biofeedback machines in somewhat the same way that you rely on your scale or thermometer. Their machines can detect a person’s internal bodily functions with far greater sensitivity and precision than a person can alone. This information may be valuable. Both patients and therapists use it to gauge and direct the progress of treatment.

For patients, the biofeedback machine acts as a kind of sixth sense which allows them to “see” or “hear” activity inside their bodies. One commonly used type of machine, for example, picks up electrical signals in the muscles. It translates these signals into a form that patients can detect: It triggers a flashing light bulb, perhaps, or activates a beeper every time muscles grow more tense. If patients want to relax tense muscles, they try to slow down the flashing or beeping.

Like a pitcher learning to throw a ball across a home plate, the biofeedback trainee, in an attempt to improve a skill, monitors the performance. When a pitch is off the mark, the ballplayer adjusts the delivery so that he performs better the next time he tries. When the light flashes or the beeper beeps too often, the biofeedback trainee makes internal adjustments which alter the signals. The biofeedback therapist acts as a coach, standing at the sidelines setting goals and limits on what to expect and giving hints on how to improve performance

The three most common methods of biofeedback include:

• electromyography (EMG) biofeedback: measures muscle tension as it changes over time
• thermal or temperature biofeedback: measures body temperature changes over time
• electroencephalography: measures brain wave activity over time

Other types of biofeedback include:

• galvanic skin response training: measures the amount of sweat on your body over time
• heart variability biofeedback: measures your pulse and heart rate

How It Works