If you're abything like me, you'd know that there's nothing more comfortable and blissful than the thought of being tucked up snug in your warm bed with your head under the blankets, lights turned off, listening to the sound of a thunderstorm or blizzard outside rocking your bedroom window.

As it turns out, most people love the thought of this, as evident by all those "rain sounds for sleeping" videos on Youtube. Why is that? What is it about this scene that relaxes us so much? Does it provide a sense of security for us to settle down to?