I have all those cognitive issues, too, but started drinking Coconut Milk (canned), cookimg with Coconut Oil, and taking MCT Oil capsules (coconut oil derivative).
My scores on the 3 hr. neuro-cognitive test have improved for the past 2 yrs. & i can tell an improvement in brain functioning in so many ways.
There are SO MANY BRAIN-HEALTHY things we can do to help: brain games, socialization, other brain healthy foods: walnuts, almonds, avocados, dark green salads, spices (such as tumeric, nutmeg, cinnamon), stayimg active, and like you said, HUMOR!
I try to stay positive by finding even little things to make me happy: pretty pictures, going outside looking at nature, reading cartoons, etc.
Afterall, its MORE FUN to be HAPPY than sad.