I've seen Alzheimer's at its very worst. The eventual loss of mobility, madness, violent behaviour, and most of all, memory loss of loved ones. No one is exactly sure how to avoid it, however it's always advisable to exercise not only your body, but your mind as well. Memory games, Soduku, crossworlds, trivia, card games are all examples of small things a person can do to keep the mind active.
If you're a visual person there were a number of hit games in the 90's. Myst, a first person mystery adventure game created by Robyn and Rand Miller was first released in 1991 for Macintosh. The game quickly gained momentum, becoming a surprise hit that expanded into a series for Microsoft Windows and other platforms.
With beautiful exotic locations, the player is "dropped" onto the island of Myst in the role of a "Stranger". Like peeling layers of an onion, the player must find clues to discover the back-story of characters bit by bit. With no violence, time limit, or obvious enemies, the game must be solved by logic and patience. Mystery lovers paradise.
Recommended Ways of maintaining a healthy mind:
Reading, playing an instrument, or learning a new language
Take different routes home and to work
Brain teasers and strategy games
Observation. Lovin' mystery is a good thing after all. The 5 w's to solving crime. Who, what, where, when, and why!