It’s not something that works 100% of the time unfortunately. I used to work as a research assistant for a geriatric psychiatrist. We were part of several clinical trials including one that tested the effects of positive actions on Alzheimer’s. People in the positive action group were asked to exercise. We had a book club and card games for mental stimulation. For the most part the positive actions group fared better than any of our other trials. This is an average though and there was a wide range of individual results.

It’s also worth noting that this was 10+ years ago and everyone eventually succumbed to their illness. Progression was slower on average for the active group and self reported sense of well-being was higher. Still not great, but better than it could have been.