Art by smbc-comics
Consciousness is often said to disappear in deep, dreamless sleep. We argue that this assumption is oversimplified. Unless dreamless sleep is defined as unconscious from the outset there are good empirical and theoretical reasons for saying that a range of different types of sleep experience, some of which are distinct from dreaming, can occur in all stages of sleep.
Pubmed Articles
Does Consciousness Disappear in Dreamless Sleep?
Sciencealert Article We Were Wrong About Consciousness Disappearing in Dreamless Sleep, Say Scientists
I think that most people aren't afraid of death itself. It's more the suffering to get there.
The most scary stuff is just not doing or experiencing anything after death, at least for me. (Probably the biggest fomo on earth)
Life is a series of missed opportunities. When you choose to do something, you miss out on a multitude of other options. That is fine.
But I get the FOMO, it took me a few years of active mindfulness to reign it in.