The body is internally associated with the mind. The body is a counterpart of the mind. It is a gross visible form of the subtle and invisible mind. Every change in thought makes a vibration in the mental body and this, when transmitted to the physical body, causes activity in the nervous matter of the brains. This activity in the nervous cells causes many electrical and chemical changes in them. It is thought activity, which causes these changes. When the mind is turned to a particular thought and dwells on it, a definite vibration of matter is set up. Often it is seen that more of this vibration is caused, the more does it tend to repeat itself, to become a habit or to become automatic. The body follows the mind and imitates its changes. In recent years a new and increasingly popular phenomenon known as biofeedback has come. It has become possible with the advent of finer electronic technology, printed circuits, solid-state circuit, and so on. In the early days of its history, it was pretty much confined to the research laboratories of various medical and psychological institutes. Now, because of advances in electronics, a simple, inexpensive biofeedback monitor can be purchased by anyone. These machines have become more and more familiar ever since their thrust into the popularity stream of the 1960s. It is being used to learn how to control an array of disorders such as headaches, high blood pressure and poor circulation. Through the use of instruments which record the body`s minute electrical signals and feed them back in amplified form through a tone or some visual indicator on the machine, it`s possible to be aware of certain changes in the internal body processes, to act on them and change the signal. In this process high tones indicate considerable tension while lower tones indicate more relaxation. The aim is to reduce the tone by relaxing.

It is important to note that these machines are used for the purpose of learning relaxation techniques and in no way can they propel one into higher states of consciousness.