The biofeedback is a feedback to a physiological function of the body.
A simple example of biofeedback is learning motion in front of the mirror. Exercise is controlled by vision and refinement is done, done again and again.
There are many applications for biofeedback. One is the use for medical purposes, the most important is the rehabilitation after the loss of some function.
The use of biofeedback complements medical treatment. Muscle biofeedback (EMG) measures and evaluates muscle tension. For example, it helps to learn how to relieve and eliminate stress-induced muscle tension.
Many diseases cause muscle weakness and paralysis. For example, paralysis caused by stroke (stroke), urinary problems due to weakening of the pelvic floor muscles (incontinence). The biofeedback device continuously monitors the contraction of the muscles during rehabilitation exercises. Feedback can be used to learn the most accurate movement.