What is it that makes one's spine tingle? For me, it's like a little spurt or rush or zing of energy from about mid-back, upwards through my neck, ending where my headbone connects to my neckbone. At the exact moment it completes its journey, my neck hairs stand on end.
Mostly it happens when I'm listening to music. It happened when this happened. Sometimes it happens with a thought. Sometimes it happens from the visual cortex - like seeing the Milky Way stretching across the night sky.
In the case of this post, it happened when I first listened to this song.