Biofeedback is a non-medical process that involves measuring a subject’s specific and quantifiable bodily functions such as blood pressure, heart rate, skin temperature, sweat gland activity, and muscle tension, conveying the information to the patient in real-time. This raises the patient’s awareness and therefore the possibility of conscious control of those functions.
By providing the user access to physiological information about which he or she may be unaware, biofeedback may allow users to gain control of physical processes previously considered an automatic response of the autonomous nervous system. Interest in biofeedback has waxed and waned since its inception in the 1960s; it is, however, undergoing something of a renaissance during the early 21st century, which some experts attribute to the general rise in interest about all alternative medicine modalities. Small biofeedback machines are becoming available for use in the home.