This feature is part of Music and Your Mind, a series exploring how music affects your brain. Read part 1 on behavior and part 3 on torture.
(CNN)"People told me, 'You are changing me.' 'You are healing me,' " Emma Smith said.
This is the feedback Smith receives on her YouTube videos, which compile gentle sounds created by touching, tapping or stroking objects, such as hairbrushes and books.
These sounds can create an autonomous sensory meridian response, or ASMR. This is a tingling sensation, usually starting in the crown of the head and moving to other parts of the body.
"Everyday objects all have a sound," Smith said.
The experience is caused by a range of "triggers," including whispering, soft speaking, tapping, scratching, slow hand movements and close personal attention, reports one of the few studies into this phenomenon.