The Brain: Use It or Lose It
Your brain is a thinking organ that learns and grows by interacting with the world through perception and action. Mental stimulation improves brain function and actually protects against cognitive decline, as does physical exercise.
The human brain is able to continually adapt and rewire itself. Even in old age, it can grow new neurons. Severe mental decline is usually caused by disease, whereas most age-related losses in memory or motor skills simply result from inactivity and a lack of mental exercise and stimulation. In other words, use it or lose it.
Books
The Monty Hall problem & other puzzles by Ivan Moscovich
Broccoli for the brain : 90 puzzles and exercises to boost your brain power by Michel Noir
Sudoku easy to hard : 100 wordless crossword puzzles. Volume 2 presented by Will Shortz
And More
New York Times Numberplay
Puzzles.Com
Lumosity
Word Games
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