Two kinds of 200 crossword puzzles presented in this mind challenging book: empty puzzles with a starting word and partially missing letters filled puzzles. In both cases the list of solution words given, but not the position. The brain is the most complicated and mysterious structure in the known universe. The truth is that we know very little about how it works. In recent years, scientists have begun to pay more attention to the brain. Studies have shown that there is health benefits derived from working crossword puzzles, because your brain needs regular playtime to form new patterns and complex neural networks naturally. Your mind requires nurturing just like your body. After all, exercise is not just about jumping jacks and free-weights; both our bodies and our minds need stimulation and exercise. Alzheimer's disease is a degenerative disease of the brain cells that results in memory loss. It leads to dementia that affects the functions of the brain associated with speech, language, decision-making, judgment, thinking, and perception. This condition is more common in people over the age of 65 and there is no known cure for it. The only method of treatment is slowing the progression of the disease, which can be partially achieved by exercising the brain by doing crossword puzzles. Crossword puzzles have proven to stimulate memory and possibly help the mind avoid Alzheimer's disease. They are also valuable in helping someone with Alzheimer's disease relearn some latent skills. Benefits of Working Crossword Puzzles Improves Cognitive Reserve Novelty and variety are crucial components of cognitive reserve - the brains ability to learn, and reserve what is learned, in the brain. Crossword puzzles are tools giving users a rigorous mental workout. Scientists have found the neurological equivalent of an un-toned body could lead to a drastic dulling of cerebral powers. Improved Focus and Attention Scientists have found that the brain actually reorganizes itself in response to new challenges, and a crossword puzzle provides such a challenge. Solving puzzles improve focus and attention. Finding solutions requires a certain amount of solitude without distraction and with concentrated attention. Increased Mental Stimulation Cognitive stimulation occurs while doing puzzles. To complete a word puzzle, one must read the words to solve the puzzle. Puzzles require brain exertion (exercise). A puzzle helps stimulate brain thinking and memory, as well as brain activity. Thus, working puzzles can increase mental stimulation. The brain is resilient and malleable, so people can slow down the progression of dementia and increase their cognitive ability by stimulating brain activity. One way is to do so is to work word puzzles because they involve hunting and comparing words, spelling, logic of space and placement, and rational thinking. Improved Memory Word puzzles have been proven to stimulate memory. When the puzzle solver tries a possible solution and it does not work, they need to remember the wrong attempt so that they do not retry a wrong answer. Many studies have shown that individuals who regularly do crosswords and similar activities have improved memory. In addition, there is less memory loss at advanced age, as well as delayed onset and reduced risk of conditions such as Alzheimer's disease.