This article was updated on September 22, 2021.
It isn’t really understood why some older populations are more resistant to aggressive cognitive decline than others. There are theories and correlative biomarkers, but the only thing certain is that it happens to all of us to some degree or another eventually.
A team of researchers from Institut Polytechnique Paris, Ludwig-Maximilians-Universitat München, and Erasmus University may have located the general age when our brain function begins to peak and decline.
The data was derived from 125 years worth of chess competitions and was published in the Proceedings of the National Academy of Sciences.
Given that chess requires memory, fluid intelligence, and concentration capacity from its subscribers, it follows that one’s proficiency in it can provide insights into one’s cognitive health.
According to the metrics employed by the authors of the new report, mental function generally peaks at the age of 35 and then begins to progressively decline around 10 years later.
“Despite evidence for an increasing importance of cognitively demanding tasks in the workplace, little is known about the life cycle performance in such tasks, particularly over the long run, ” the authors wrote in the new paper. “We estimate the life cycle patterns of cognitive performance over the past 125 years using a methodology that is based on the comparison of individual move-by-move performance of professional chess players relative to the best move suggested by a chess engine in a given configuration.
The findings document a hump-shaped profile of performance over the life cycle and an increase in individual performance, particularly at younger ages, that is associated with dynamics across birth cohorts rather than over time.
Life cycle patterns of cognitive performance over the long run
The researchers analyzed chess performances from 24,000 different professional matches that occurred between 1890 and 2014. Collectively, these matches featured 4,294 competitors. Twenty of these were classified as world champions of the sport.
Each participant was paired with a computerized chess engine designed to produce optimal moves in any given scenario. Thanks to this control measure, as a participant aged, researchers could gauge their ability to assess their opponents.
Irrespective of initial performance level, players tended to develop very quickly up until the age of 20. After this, growth continued but at a significantly slower pace and ultimately peaked around the age of 35.
Deterioration was subject to a slightly higher number of variants, but the vast majority of the study pool evidenced gradual cognitive decline after the age of 45. This represented a “hump-shaped age cycle.”
This patterned curve was altered over time. Meaning, players appeared to develop at a quicker pace toward the end of the 20th century. The authors theorize this has to do with the availability of online chess courses and media.
There are likely comparable factors that will influence the rate of cognitive decline in modern populations.
“In sum, we presented an analysis of the long-run changes in life cycle profiles of cognitive performance based on panel data with repeated observations of the same individuals over their life cycle using an identical task, chess, and fully comparable performance evaluation across individuals,” the authors conclude.