So, as the cells depolarize within the essay node, they generate an impulse, an action potential that moves within the atria of our heart. And as it moves within the two atrium of the heart, it causes those atria to actually contract. So the essay node basically initiates its own action potential without the input of our autonomic nervous system. And that's exactly why the essay node is commonly referred to as the natural pacemaker of the heart. It generates an action potential in the right atrium, which then moves into the left atrium and eventually into our two ventricles. So it triggers a set of electrical events within the heart that causes the heart to actually contract and pump all that blood through the blood vessels of our body.