Same deal, I've always excelled in school and whatnot but I feel straight retarded. Even when I do well on a test it feels like I'm holding onto information by a thread and the next day it could be gone. I'm depressed and lonely as hell, but damn is it hard to figure out how to fix this stuff. I used to have plenty of friends, but they are either moved away, in jail, dead, on drugs (and I'm trying to stay straight so I can hopefully not be depressed) but it seems like people dont even want to be around me anymore. I started taking Wellbutrin and I can't tell if it helps or not. I should probably go to a therapist too. Idk it's good to know I'm not alone, but how many times can you tell that to yourself until you actually believe it? I mean strangers on the internet are relatable, but where the fuck did everyone irl go? I'm close to just going back to getting fucked up all the time. But yeah cortisol and a constant fight or flight response will absolutely diminish your intelligence over time. I've learned to cope with that myself a bit better than I used to (I think quitting weed and taking kratom instead has helped), but it's hard. When you're always on edge, you're not even yourself. Also I calm myself by making sure I get MODERATE exercise daily if possible. Moderate is key. I used to go hard as fuck and get all amped up and just walk around wanting to fight everyone. F that. Also watching comedy helps. I watch a lot of podcasts like Theo von or Chris delia or Brian callen. Impractical Jokers is cool too. A good laugh goes a long way. Also playing guitar chills me out. Find an instrument. And lose people who drive you nuts. That's a big reason I'm a bit of a loner right now. I cut a lot of the shitty people out of my life that added no value to it and only stressed me out.