Hi Tucson,
This sounds very frustrating.
I have increasing fogginess and some cognitive deficits with some meds. I get it right now from Lamictal, for example. I find cognitive deficits also vary with the course of my illness.
I know I often get concerned I'm starting to experience dementia.
I must tell you that your posts here are very well reasoned out... and often make me stop and think about my own stance on various topics. I am so often impressed by your reasoning abilities. I don't know if it helps for you to know this or not? I hope it does help.
Have you considered testing, like a neuropsychiatric evaluation?
It's great to have your contributions here at PC.
I hope you can get these concerns sorted to your satisfaction.

WC