Currently, word puzzles and vitamin supplements are thought (at least to the mainstream) to stave off cognitive decay that comes with ageing. However, a new study challenges that popular notion, finding that when the elderly are enrolled in a 14-week (or a semester-long) course, the cognitive benefits outweigh those caused by doing mere puzzles.

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The study seems to be well structured, and if repeated on a large scale with the same findings, could change the way we combat mental decline.