I have been a long hauler now for something like 19 or 20 months. I unfortunately still struggle with brain changes. At this stage I feel like the worst brain changes are cyclical so I think there is more to it like when I'm stressed or not sleeping good enough or don't have enough time to relax. My worst issues are short term memory issues and word recall, also for some reason when I am driving at times for a moment things don't look familiar or I forget how to get where I'm going. I went through the cognitive testing and everything there was fine. Basically, they just recommended getting enough good sleep, meditation, exercise, eating healthy, reducing stress, laughing more, finding time to relax, etc. Good luck to you.