Biofeedback tries to teach you to control automatic body functions such as heart rate, muscle tension, breathing, perspiration, skin temperature, blood pressure and even brain waves. By learning to control these functions, you may be able to improve your medical condition, relieve chronic pain, reduce stress, or improve your physical or mental performance (sometimes called peak performance training).
During biofeedback training, sensors attached to your body detect changes in your pulse, skin temperature, muscle tone, brain-wave pattern or some other physiological function. These changes trigger a signal a sound, a flashing light, a change in pattern on a video screen that tells you that the physiological change has occurred. Gradually, with the help of your biofeedback therapist, you can learn to alter the signal by taking conscious control of your body's automatic body functions.