We don't. tDCS is in its infant stages but because it's easy to do there is a TON of research coming out. Low hanging fruit is as treatment for depression. Much

We don't. tDCS is in its infant stages but because it's easy to do there is a TON of research coming out. Low hanging fruit is as treatment for depression. Much harder is any kind of cognition enhancement. DIY tDCS has been around for a few years, but this is the first example of tDCS self-science that at least tried to collect useful data (that I'm aware of).