I have listened to more overnight and I understand it to be the physical reaction to your heart awakening - your heart centre is open and this is where the 3rd energy or unconditional love eminates from...I notice it happens often when I feel that woosie giddy feeling of love not just for myself or my love but in social situations where I'm feeling it for all - sometimes my moonstone pendant is so hot it feels like it has been baking in the sun lol