The intent of this blog is (and has always been) to correlate brain fitness with puzzles. I was asked recently, if doing puzzles helps stave off Alzheimer's and other forms of mental deterioration. I would like to share the thoughts I passed on to this particular reader with all readers of this blog. Alzheimer's is a brain disease that causes increasing loss of memory and other mental abilities. It is the most common cause of severe memory loss in older adults. It attacks very few people before the age of 60, becoming increasingly common thereafter. In the not-too-distant past, older adults suffering from severe memory loss were often labeled "senile." But it is recognized today that they were probably suffering from Alzheimer's. The disease is named after Alois Alzheimer, a German psychiatrist, who first described the effects of the disease on brain cells in 1907.
As a brain disease, Alzheimer's raises the question of whether or not non-clinical intervention strategies, such as puzzle activities, can be of benefit in helping to prevent it. A number of researchers have investigated this possibility and their research has led certain organizations, such as the Alzheimer's Association in the United States, to endorse puzzles as part of a preventive strategy approach against the dreaded disease. The best known of the published studies is the one that came out in 2003 in The New England Journal of Medicine (volume 348, pp. 2508-16), which strongly suggests that puzzle activities, such as crosswords and board games, may indeed help prevent dementia. The study found that 469 participants (aged 75 and older) who did puzzles, games, and engaged in other activities for about four days a week were two-thirds less likely to get Alzheimer's when compared to those who did these activities once a week or less, or not at all. It would seem that any mentally challenging activity spurs the brain to establish new connections or even to grow new brain cells. This extra brainpower may compensate for any loss of brain cells due to the aging process.
However, I should mention that the literature on the correlation between puzzles and brain fitness is not extensive and, when looked at with a critical eye, really does not establish a definite correlation. In his excellent 2009 book From Square One: A Meditation, with Digressions, on Crosswords, Dean Olsher claims that even those who have found a correlation between crossword puzzles and mental acuity admit that the two are only marginally related. The reason is that doing a certain genre of puzzle over and over, as most people are inclined to do, does not provide enough diversity for the brain. The point is a well taken one. The brain does indeed seem to need many kinds of stimulating inputs in order to keep functioning. A certain puzzle genre by itself, such as crosswords, can be only a small part of the overall "input software" the brain might need to fend off or delay serious deterioration. Music, reading, and other brain-based activities should certainly be programmed into this software. Nevertheless, it is my personal opinion that any puzzle, even one with which we have become familiar, will contribute to keeping the mind sharp to varying degrees. Individual brains differ significantly, depending not only on genetics, but also on life experiences and individual talents. The fingers activate the same general area of the cortex in everyone's brain. But this area is larger in people who use their fingers often-for example, people who play musical instruments such as the piano or the violin. So, by extension, one can argue that the areas of the brain activated by puzzles of particular kinds might be larger than normal. I do not know this as a fact. But it certainly seems to me to be a logical assumption. It would be nice to see studies conducted on this very possibility.
In a series of studies and interviews that I conducted myself with the help of my students at the University of Toronto, I discovered that we do indeed all have different puzzle preferences and problem-solving abilities. Some people love only crossword puzzles, others just logic ones (like Sudoku). A few enjoy a mixture of them. Like literary and musical genres, we seem to have specific preferences when it comes to puzzles. Those who do Sudoku regularly told us that they couldn't get enough of it; similarly, those who do crosswords all the time told us the exact same thing. Following up on this study with my students, we used puzzle materials with the interviewees that fell into the "unpreferred" category. So, with those who disliked crosswords, we got them to do crosswords over 8 months; and to those who hated math puzzles, we gave them math bogglers to do. At the end of the period we found that a significant number (around 74%) claimed that they started to like the puzzle genre they once disliked. By simply doing puzzles, our "puzzle instinct" seems to kick in and allow us to enjoy all genres. I would love to see a controlled experimental study that would examine this "puzzle diversity hypothesis" more scientifically, as it may be called. My guess is that the results would be highly supportive of it.