So once the AV node delays the signal, it depolarizes and sends the electrical signal through the bundle of his and our PerkinsI fibers that essentially permeate through the walls of our two ventricles, as shown by these purple fibers within this diagram, this does not actually cause any contraction. Now let's move on to this segment, the QRS segment, which is commonly known as the QRS complex. And this complex actually consists of three individual waves. We have the Q wave, the R wave, and the S wave. Now, the Q wave and the Swave are known as the downward deflection waves because they actually decrease our voltage. They make it more negative.