Biofeedback is a kind of feedback that a person can obtain from special equipment in real time, to make him or her aware of the bodily processes such as blood pressure, heart rate, skin temperature, sweating, and muscle tension, in order to develop the ability to consciuosly control the related physiological activities.
Biofeedback systems have been known in India for millennia. Ancient Hindu practices like yoga and pranayama (breathing techniques) are essentially biofeedback methods. Many yogis have been known to exercise control over their physiological processes.
Some yogis are able to do that without the use of equipment, but biofeedback training allows users, through outward visual or audio signals, to gain control over physical processes previously considered automatic. It helps survive in extreme or hazardous situations, and it also is beneficial in treating certain ailments, such as stress, migraine, tension headaches, high blood pressure, heart trouble, insomnia, muscular tics, and anxiety.
Some types of biofeedback instrumentation include:
Electromyogram (EMG) - the most common form of biofeedback measurement. An EMG uses electrodes or other types of sensors to measure muscle tension alerting you to muscle tension so you can learn to recognize the feeling early on and try to control the tension right away. EMG is mainly used as a relaxation technique to help ease tension in those muscles involved in backaches, headaches, neck pain and grinding your teeth.
Galvanic skin response training - sensors measure the activity of your sweat glands and the amount of perspiration on your skin alerting you to anxiety. This information can be useful in treating emotional disorders such as phobias, anxiety and stuttering.
Electroencephalography (EEG) - monitors the activity of brain waves linked to different mental states, such as wakefulness, relaxation, calmness, light sleep and deep sleep. The user learns when he or she is producing the alpha waves also produced in meditation.
Biofeedback opens possibilities of self-healing, however it should not be taken beyond relaxation without a doctor, to avoid damaging the vital organs.