How do people sharpen their mind?

Right so, as some of you may know. I’m a bit fucked up. For those that don’t. I have

Cystic Fibrosis Double lung transplant I also had some seizures that caused some brain damage too Broken spine Brain damage And just recently beat stage 4 Lymphoma.

Now, as some of you know, a lot of the meds you’re on after transplant slows your thinking, and now, with having done Chemo, my thinking is even slower.

So my questions are.

Has anyone else experienced this? If so, did you do anything to help sharpen your mind? If so, what stuff did you do?

I know we can’t take some of those Herbal remedies due to the possibility of interactions with our meds. But I’m just tired of being spacey.

My memory is also shit because of all this. Thankfully I have a very patient wife. There are so many times she will ask for something simple to be gotten or done and the second she stops speaking, I forget what she asks, almost immediately.

And after 8 and a half years of transplant, I find it getting worse. I’m unsure if the chemo sped the process up.

I’m open to try any and all suggestions that are safe.