Biofeedback is a form of alternative medicine that involves measuring a subject's 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 conscious control of their unconscious physiological activities. By providing the user access to physiological information about which he or she is generally unaware, biofeedback allows users to gain control of physical processes previously considered an automatic response of the autonomous nervous system.
Neurofeedback (NFB), also called neurotherapy, neurobiofeedback or EEG biofeedback (EEGBF) is a therapy technique that presents the user with realtime feedback on brainwave activity, as measured by sensors on the scalp, typically in the form of a video display, sound or vibration. The aim is to provide real-time information to the Central Nervous System (CNS) as to its current activity. Some approaches believe that conscious understanding and mediation of that information is important for the training process; however, this claim has never actually been verified.
Those approaches also believe that neurofeedback training can be understood as being based on a form of operant and/or classical conditioning. In that frame of reference, when brain activity changes in the direction desired by the trainer directing the training, a positive "reward" feedback is given to the individual, and if the change is in the opposite direct from what was intended, then either different feedback is given or the provision of otherwise attained "positive" feedback is inhibited (or blocked).
These ideas can be applied in various combinations depending on the protocol decided upon by the trainer. Rewards/Reinforcements can be as simple as a change in pitch of a tone or as complex as a certain type of movement of a character in a video game. This experience could be called operant conditioning for internal states even though no research has yet demonstrated that clear operant response curves occur under those scenarios.