I have direct experience with this (I'm in the process of recovering right now)
2 weeks ago I rolled, taking 6 or 7 pokeballs (good quality pills)
Anyways, I seriously pay attention to changes in my cognitive/critical thinking abilities.
Right now, I am on summer break, so I have pretty much no stress in my life at all and have all the time I need to sleep and take care of myself.
So anyways, here is my experience:
For the first few days (like 3 or 4 days) I was having some insomnia, and took lots of 5htp (like 200mg a night) and some melatonin to help me sleep. During this time all I needed was like 5-7 hours of sleep a night
Anyways, eventually, around day 4 or 5 I was much less stimulated and it was easier for me to get to sleep, so I stopped taking melatonin and 5htp.
Around the 5-6 day mark I started eating more then normal, and sleeping more (getting like 8-10 hours of sleep a night)
So anyways, fast forward to this last wednesday (1.5 weeks). I woke up after sleeping for 9 hours, and immediately noticed that I had my critical analysis skills back, and that I was much sharper then any of the previous days (almost as sharp as before I rolled).
My critical thinking skills began returning throughout the consecutive days after day 10.
So now fast forward to today (around 13 days later), I feel pretty much normal. I don't feel just quiet there, but I am pretty much as sharp as I was before I rolled (like if I "scan" my brain, I can still feel something is a bit off)
Anyways, I've been trhough this process a bunch of times, and usually by the 2.5-3 week mark, you are pretty much back to normal (your critical thinking skills get better and better every day)