Have you ever listened to music and it gives you "chills?" This response is called a "frisson," a french word meaning "to shiver."
When I want to access certain emotional and inspirationally charged visualisations I get frissons that I can create or stop at will. I practice this exercise when I need a quick energy/mood boost. It feels very calming and relaxing, as if pure wave-like energy is ebbing and flowing - pulsating throughout my body.
$(1)$ What percentage of people experience frissons?
$(2) $ What percentage of people can create frissons at will?
Wikipedia says about this topic:
Frisson (French for 'shiver') is a sensation somewhat like shivering, usually caused by stimuli other than cold. It is typically expressed as an overwhelming emotional response combined with piloerection (goosebumps). Stimuli that produce a response are specific to the individual. Frisson is of short duration, usually no more than 4–5 seconds, usually pleasurable.[1] Typical stimuli include loud passages of music and passages that violate some level of musical expectation.[2]
Found this article about "voluntary piloerection:"
https://www.inverse.com/article/42005-goosebumps-control-voluntary-piloerection