The prana, well actually, even physically speaking, the oxygen that passes through the lungs, is brought into the blood stream, but after passing through the blood stream it passes into every cell of the body, including the nerves. There are certain asanas in yoga that are absolutely essential to bring vitality in the different nerves, that means in the whole network of nerves, and in the centers. And many of the practices that we've been doing in the seminars are to develop the chakras, which are the centers of the whole nervous system.