2
Shit faint
(lemmy.fmhy.ml)
A "Showerthought" is a simple term used to describe the thoughts that pop into your head while you're doing everyday things like taking a shower, driving, or just daydreaming. A showerthought should offer a unique perspective on an ordinary part of life.
Vagal tone, is the technical answer. A nerve (vagus) runs through your body and, among other things, slows the heart. When straining to "void", you cause that nerve to activate more strongly. It's also related to the Valsalva maneuver.