This practice uses machines or other devices to provide audible, visual, or tactile information about body processes that frequently are under subconscious influence.
This feedback can be as simple as holding a piece of tape that changes color when someone successfully practices a relaxation technique and warms their hands.
In contrast, some very sophisticated computer programs allow a person to proceed in a computer game when their brain waves shift in a certain manner. Somewhere between these levels of technology are machines that provide light or sound feedback when a person successfully relaxes a muscle, lowers blood pressure, or lessens nervous system stress measured through changes in electrical conductance of the skin.
Read more: Yoga, Tai Chi & Qi Gong