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 kept a dream journal for a couple of years.
Subjectively there was no way for me to know if it was memory or just my tired brain making a story out of the left over bits of sleep.
It did fuel a lot of creative writing though (both in and out of the journal). And helped me be more in touch with my emotions.