And so this will begin to become more positively charged. And remember, as the inside of the cell initially becomes more positively charged, that will begin to stimulate the opening of the sodium ion channels, the sodium voltage gated channels. So what that basically means is we stimulate the NA channels to open up adjacent to where the stimulus actually took place. So to see what we mean, let's take a look at the following diagram. So, as soon as the sodium channels begin to open up on the adjacent region, the sodium channels where the stimulus actually took place begin to close. And as they begin to close, that will basically inactivate our sodium channels and that will open up the potassium channels.