The closest I get to that is when I am getting a massage actually. If I get a 90 minute one, about halfway through my brain stops racing and I enter this, not quite hypnogogic, state where things are quiet and fluid and peaceful. The closest thing is waking up after a good night's sleep with an empty brain before the weight of the world comes crashing in.

My understanding is this is the default mode network allowing your brain to process things. I think modern life just completely inhibits any amount of this happening and that’s why these things are so important