We have, through time, developed and used instruments that help us detect the presence of harmful, dangerous activity in our environment so that we can then respond appropriately. Since the early 1960’s, there has been considerable research in the development of instruments and techniques for determining the same in human beings. The process has come to be called, “biofeedback.”
<?xml:namespace prefix = o /> It is useful to consider the term, “biofeedback” as meaning, “body signals.” These body signals represent our on-going physiological states; and their measurement, communication and change is the concern of biofeedback practitioners and researchers. In practice, biofeedback is a tool for physiological self- instruction. It is a method for teaching someone how to relax in the presence of stressful events. In the process, one learns to gain voluntary control of physiological processes such as muscle tension, blood flow (temperature), heart rate, blood pressure, sweat gland activity, and brain wave activity.
 The internal stress reported by biofeedback instrumentation is generally a reaction to on-going events in one’s life. Biofeedback training facilitates self-regulation of that reaction through the use of sensitive instruments which monitor changes in the body. It is believed that learning to modify these stressful reactions can alleviate certain disorders. Additionally, biofeedback can also enhance the ability to relax and create more pleasurable states of consciousness. The types of difficulties, occurring as some form of stress reaction, that have been studied, measured and treated using biofeedback instrumentation and procedures include: Muscle tension, headaches (both migraines and tension), blood pressure problems, anxiety, depression, jaw pain, sleeplessness, temperature-related problems such as Reynaud’s disease (cold extremities), hyperhydrosis (profuse sweating), and hyperkinesis in children, to name a few. There have even been reported successes with muscle rehabilitation of paralyzed victims, seizure disorders; and alleviating some spasmodic rigidity associated with cerebral palsy.
 The process of biofeedback provides information to an individual about on-going internal activity and then provides training for its modification. As physiological changes are the desired outcome in biofeedback training, it is frequently important from the start to involve a physician– especially if a person is receiving medication for a medical problem. During the training, the instrumentation is applied to some stress points on the body with unique sensors. The sensors then measure a particular type of internal activity (i.e., muscle tension, temperature, etc.), and “feed-back” this information to the individual in the form of visual and auditory signals. These signals are organized into recognizable patterns, and the task is to alter a pattern with and without formal instruction.
 Biofeedback instructions encourage a person to alter breathing patterns, degree of muscle tension, speech, and posture. They often involve the use of “guided imagery”, in which someone is instructed to have a specific internal experience containing certain parameters. One such example involves imagining a “warm” scene, such as a fireplace on a snowy winter’s day, until the person can begin to notice his (or her) hands becoming warmer; and body becoming heavier and more relaxed. At various points in the training, the individual is both stressed and relaxed, while being given feedback from the instrumentation. In this manner, it is possible to discriminate among different bodily states, and use the information to learn to produce and maintain a desired physiological change. In time, with practice, self-regulation of stressful reactions becomes a learned skill that is integrated in one’s daily life, so that the biofeedback instruments are no longer needed.
 Thus, through biofeedback training it is not only possible to learn to manage stress on a daily basis but, in a more generative (long-term) than remedial (short-term) sense; it is a way of taking responsibility for the prevention and control of symptoms which arise from future events in your lives.