Biofeedback is the process of gaining greater awareness of many physiological functions primarily using instruments that provide information on the activity of those same systems, with a goal of being able to manipulate them at will. Some of the processes that can be controlled include brainwaves, muscle tone, skin conductance, heart rate and pain perception.

Biofeedback may be used to improve health, performance and the physiological changes that often occur in conjunction with changes to thoughts, emotions and behaviour. Eventually, these changes may be maintained without the use of extra equipment, for no equipment is necessarily required to practice biofeedback.
Biofeedback is found to be effective for the treatment of headaches and migraines.