Weird shock sensation throughout body
I'm a 40 year old male. Every once in a while, about 1-2 times a month, I'll get a really quick shock like feeling the instantly radiates throughout my body. From what I can tell it seems to start from the back of my neck/head and radiates throughout my body and lasts about half a second. It's very instantaneous and doesn't hurt at all. It just feels weird. It happens when I'm relaxed. Typically sitting in a chair laying in bed reading or watching TV. This has been happening for a few years. I've had several physicals and associated blood tests and everything is fine. I've had my hormones checked with no issue. I did have hairline fractures in 2 of my neck vertebrae about 20 years ago. But, it never really gave me any issues.