The road to superaging is difficult, though, because these brain regions have another intriguing property: When they increase in activity, you tend to feel pretty bad – tired, stymied, frustrated. Think about the last time you grappled with a math problem or pushed yourself to your physical limits.
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This means that pleasant puzzles like Sudoku are not enough to provide the benefits of superaging. Neither are the popular diversions of various “brain game” websites. You must expend enough effort that you feel some “yuck.” Do it till it hurts, and then a bit more.
Lisa Feldman Barrett, “How to Become a ‘Superager’“