I get these sensations, now called ASMR, when I hear typing or knitting. It's like having your hair stroked and is relaxing and pleasurable. Some of the noises that others love, like whispering and tapping tails I can't abide though.
I have what can only be described as electric flashes I n my head. I had an operation for an aneurysm and have been in the past described as a nurotic only because my mum was manic depressive. I had an opportunity for a very bad cranial aneurysm. Pp
I was reading a thread somewhere about the strange sensations some people experience, in their heads. This article www.bbc.co.uk/news/magazine-35106835 might help to explain why, and what causes them.