I have been wondering about the same thing too (although I don't like that word much). "Brain fog" is something that I can relate too and I would be happy to find a way to fight here.
Unfortunately it is difficult to sort things out. If we start from the wikipedia page, some of those things are just expensive scams, some are not well researched and may or may not work, some are well known but limited in effect, and some are prescription drugs that might be dangerous to use without medical oversight. Most of them are expensive. And obviously, I expect the effects to vary much with the user. Did anyone experiment with anything interesting here ?
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ouroboros
A bit obsessed with vocabulary, semantics and using the right words. Sorry if it is a concern. It's the way I think, I am not hair-splitting or attacking you.