http://en.wikipedia.org/wiki/Autonom...idian_response
Autonomous sensory meridian response (ASMR) is a neologism for a recently-described perceptual phenomenon characterized as a distinct, pleasurable tingling sensation in the head, scalp, or peripheral regions of the body in response to visual, auditory, olfactory, and/or cognitive stimuli. The nature and classification of the ASMR phenomenon is controversial. Tom Stafford, a professor at the University of Sheffield, says, "It might well be a real thing, but it's inherently difficult to research."
http://www.youtube.com/watch?v=RVpfHgC3ye0