Yes. In my opinion neurogenesis and mania/positivity is tightly linked.

https://www.technologynetworks.com/neuroscience/news/adult-n...

I have using dreams sometimes...where I can smell, taste, feel the drugs. Only to wake up feeling disgusted and ashamed. Beneficial? Maybe, maybe not.

You've never had night terrors? I'm not sure how those would be classified as beneficial.