Biofeedback uses electronic equipment to monitor bodily functions that are normally thought to be outside of conscious control so that you can gain voluntary control of those functions. Biofeedback includes modalities such as finger temperature, skin conductance (sweat gland activity in the hands), heart rate and heart rate variability, respiration and electromyography or EMG (electrical activity produced by the skeletal muscles).
Biofeedback has a long history and its efficacy is demonstrated in numerous studies. A documentary about its early history can be seen on youtube.com. There has been a lot of progress in biofeedback both in terms of the technology and the research. An explanation of the current state of biofeedback can be seen in another video.
Dr. McAllister has over 24 years of experience working with biofeedback modalities and has trained several therapists.