While this is undeniably impressive and hopeful, it should be noted that these are short-term affects. The article mentions this: "So far, there is no evidence of addiction at the low dose in which infusions are delivered. Ketamine does, however, have one major limitation: Its relief is temporary. Clinical trials at NIMH have found that relapse usually occurs about a week after a single infusion." It then goes on to…
A big part of depression seems to be this incapacity to even imagine any kind of robust, non-fake happiness. In bad moments one can even get paranoid: like, why is everyone going around pretending like they're happy, when they obviously cannot be? I think it's like this with any persistent mood; your whole world view is altered.
So however you find it, just a couple of hours of, say, having a conversation where you don't feel like the worst loser in the universe and the nadir of civilization, that just shows you something about life.
"Oh... I... I am just a person like these other people... I don't have to radiate horror and disgust... I can just stretch my arms right now and feel my body as an animal with the right to live and enjoy... Huh... Hah! Hahaha!"
And then the next morning maybe you feel like crap again, sure. But the understanding that these are just different mind states is so valuable. Like, for someone who really doesn't believe in anything except depression anymore, I totally understand suicide. So giving people the chance to feel something else, even just for an hour—if psychiatry can start to really do that, that's so wonderful.