The primary argument of this NBER working paper is that "employment, particularly near retirement age, can slow the rate of cognitive decline."

Would this not depend on the type of work being done and type of working conditions? Doesn't working in a boring, unchallenging, repetitive, dead-end job, dull the senses? Also, now a day, people continue to work even into their 70s, 80s, and even 90s, at least those that can find work. I don't see many people opting to retire when they have bills to pay.

Stan Lee used to say something along the lines of: “I’m not working, I’m playing!” If the job feels like fun, then the primary argument makes more sense to me. Based on past experience, however, I can relate to the later as my senses definitely got dulled, add to that compounding age-related health problems which did not help.

I try to do some Sudoku & Mahjongg puzzles at least twice a day, in my Linux machine, just to keep my mind awake.