399 Games, Puzzles & Trivia Challenges Specially Designed to Keep Your Brain Young.

399 Games, Puzzles & Trivia Challenges Specially.. Organized on an increasing scale of difficulty from “Warm-up” to “Merciless,” here are 399 puzzles, trivia quizzes, brainteasers, and word game that are both fun and engaging to play, and are expertly designed to give your brain the kind of workout that stimulates neurogenesis, the process of rejuvenating the brain by growing new brain cells.