I have the same issues: speech difficulties, memory slips. I never had speech issues or memory slips like the ones I am having before, so I know they are PCS/TBI related.

Re: stress, anxiety, my brain used to work better under pressure. I was far more articulate/spoke faster, when I was feeling the pressure. Now, my brain just stops working when I am even slightly stressed, and words get stuck, I cannot think, etc.