Anyone feel like their mental capacity has gone awol years after being diagnosed

Absolutely. I'm one month post-colectomy, and have been amazed at how much my mental sharpness has come back in that period (I'm a university professor). I was really busy in my career pre-diagnosis: publishing a lot, giving papers at conferences, lecturing etc. Post-diagnosis, prednisolone made it so hard to think, read or write. I felt like I was constantly on edge, and couldn't sit down to focus on anything. My mind felt like a very fuzzy place where nothing very profound could develop or settle. In that first pred-period, my university let me work part-time on other tasks (that didn't require as much precision thought). Once I was finished tapering that first pred-course, I went back to my normal work.

My mental focus improved when I wasn't on pred anymore, though even when I wasn't on pred, I just couldn't think as clearly as before. In my case I had a tough three and a half year battle with colitis: in year one I had two big flare ups with a few months of remission in between. Then in year two I had more of the same, with a few smaller flare ups. I remember being on pred at my brother's wedding, where I was the MC during the speeches - I even had to have my new sister-in-law's maiden name written down on card because of how hard I found it to focus on details like that (even though I knew her and her name very well beforehand!)

In those years, when I was in remission I wasn't too exhausted and was able to think fairly well. Then in year three nothing could get in control of a huge flare up (pred, asacol, pentasa, azathioprine, salofalk enemas, uceris/cortiment, infliximab/remsima...), which lasted for 18 months and led to my recent surgery. In that flare up, trying to think in much depth about anything was very difficult. At the worst point (which is when I had just started infliximab), the fatigue made it hard to choose the right words when speaking. I would know the word I meant, but another (similar sounding but wrong) word would come out.

At that point, I was having to write out my lectures word-for-word beforehand, and follow that script exactly in class (and not just the actual class material, but all the intro stuff, "Hi class, it's great to see everyone, today we're going to be doing...") because I found it hard to structure my thoughts and speech spontaneously and clearly.

I found the overall package took up so much mental and emotional energy (the uncertainty from week to week about whether I would flare up again, and latterly the constant struggle with urgency and fatigue, the investment you make in exploring treatment options, their potential side effects and possible benefits, etc).

Now, post-surgery, I've been amazed and how much easier it is to sit and read through books, try to process and express complex ideas, to write, discuss ideas with colleagues, and so on.

So, I totally sympathise with your situation. I'm glad you're feeling better for longer periods, and hope that continues for you. I think it's pretty normal that we only realise just how much our mental powers suffer during flare-ups when we are no longer in them.

I haven't seen any improvement of my mental faculties whatsoever post-surgery.

There's loads of possible reasons for fatigue/mental slowdown. If UC isn't the direct, primary cause of that fatigue, colectomy will do nothing for it.

I don't know if it's just me getting older or if it's from everything I've been thru...(severe UC, all the drugs, surgery, anesthesia, missing organs) but my brain/mental capacity has definately gone south.

I too feel very dull and tired since the onset of UC. I was never a genius before, and now my intellect's a few notches further down.

I can relate to all of this. I've been in active flare for a long time, and taking prednisone for way longer than I would like. I'm foggy, scatterbrained, and sometimes have trouble speaking correctly - my words will sometimes get jumbled, although I can type just fine. All on top of the general feeling of malaise and extreme fatigue... It's awful. I'm working full time and exhausted. Even on weekends I have trouble getting chores done, thankfully my husband is extremely supportive and is doing more than his fair share.

I'm am trying to stay optimistic that the Entyvio will work for me and I can finally get off the steroids and back into remission which should bring me back to my "old self".

Jujub - Last night was the first night in months where I actually slept through the night instead of getting up every 2-4 hours. It's amazing how much better I feel. I'm hoping this is a sign that Entyvio is helping me but I've only had one treatment so far - too early to say. And with UC I've found my symptoms still vary quite a bit day to day so I will probably have a totally different experience tonight. But I'm hoping anyway. :)

Anyone feel like their mental capacity has gone awol years after being diagnosed?

Nope, not on an ongoing basis. When I was flaring and on high doses I felt brainfog but that's the only time, it was temporary and a known side effect of that med.