In the atria, the sequence of repolarization is the same as the sequence of depolarization. As a result, the reversal of the charge distribution causes a deflection on the electrocardiogram whose polarity (or direction) is the reverse of that induced by depolarization. This repolarization deflection or wave is referred to as the T wave of the P wave (Tp). However, it is usually not appreciated because it is contained within the PR segment, the QRS complex, and the ST segment of the electrocardiogram. We will return to this later when we talk about ST segment changes.