Our Brains Begin to Slow Down at Age 24

Is 24 the new 50? If you’re going by when our intellectual skills start to decline and dull due to the passage of time, then it might be.

According to researchers at Simon Fraser University in Canada, things start going south at age 24. They came to that conclusion after studying 3,305 volunteers aged 16 years to 44 years. The participants played a real-time game that approximated everyday real-world situations that test our cognitive abilities, from concentration to juggling multiple tasks to shifting our focus from immediate to long-term issues. The game recorded the players’ moves, and researchers analyzed hours of data from it. As expected, the speed with which the volunteers made decisions, and shifted between tasks, declined with age.

Many studies have documented the gradual deterioration of cognitive skills over time. But in this study, published in the journal PLOS One, the drop, albeit small, was detected first among 24 year olds. In fact, for every 15 years after age 24, cognitive speed dropped by about 15%. And the results could not be explained by the fact that the players were getting better at navigating the game over time; the age-related decline remained, even among those with more skill playing the game.

This doesn’t mean it’s all downhill after your mid 20s. As cognitive speed slows, the brain makes up for some of the deficit in a variety of ways: by relying on experience to anticipate and more accurately predict upcoming tasks, as well as by employing mental shortcuts such as eliminating extraneous information and paring down incoming information to just core nuggets of relevant material. So while we may get slower, we might also be getting smarter. Feel better now?

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