[ntaso]

I noticed a similar phenomenon, but I'd distinguish 3 different kinds:

1. As a child (and still as an adult) I sometimes get this tingling sensation in my scalp when someone does something very mundane (e. g. when I watch the barber cutting my hair). I definitely have to be in the mood for that. So, this scalp sensation comes mostly when I see and observe something. Sometimes, it also comes when someone tells a story in a soft voice. My father could trigger that when I was a child.

2. Some music just gives me the chills. This tingling sensation is mostly "goosebumps down my neck and spine", less in my scalp. I found that "Brutal Dubstep Drops" never fail to cause it quite strongly and fast. E. g. this one: https://www.youtube.com/watch?v=LQU9RFTR_84 (edit2: this never gets old and almost always works, how weird. If you listen to it, listen at least the first 1:30 minutes)

3. If someone touches my neck or back and uses fingernails to stroke me very softly. I get goosebumps and my body doesn't get used to it for 15-20 minutes if done right.

I guess 2+3 are different from ASMR, but I definitely experienced it. Quite enjoyable.

Edit: Also this video, as cheesy as it might be: https://www.youtube.com/watch?v=zSgiXGELjbc&list=PLFC4EE4355...

I think, for me, it has something to do with fascination, mix of repetitiveness and variation, and a relaxed state of the person I observe.

[ryukafalz]

#2 is a separate sensation called frisson:

http://en.wikipedia.org/wiki/Frisson