It is not so popular anymore, but in past centuries there used to be, socially, greater respect what it means to accumulate experience in life and the opinion that older people might have solely for that fact and because they were presumed to have good judgment. This approach is now supported by research that reveals at what age the human brain reaches its maximum performance.
The meta-analysis published in Intelligence indicates that, if we understand mental ‘performance’ as the combination of cognitive skills and personality traits that predict sound decisions and career successthe peak of the human brain comes at maturity: between 55 and 60 years old.
The psychologists Gilles E. Gignac and Marcin Zajenkowskiauthors of the research, have integrated results from 9 large studies carried out between 1993 and 2025, standardized the measurements and created a composite index to locate the functional peak. The finding fits with another reality known as that peaks in professional achievement and leadership usually occur in the second half of life.
Capacities at different speeds
The key is that Not all capacities follow the same curve. The ‘mechanics’ of thinking – fluid reasoning, working memory and processing speed – peak around the age of 20 and gradually decline.
Instead, other dimensions useful for deciding well and performing in complex jobs improve over decades: accumulated knowledge (crystallized intelligence), emotional stability, responsibility (discipline and reliability), emotional intelligence, financial literacy and resistance to sunk cost bias, the latter being the ability to ‘cut losses’. That is, not continuing to invest time or money in something just because we have already invested. Evidence shows that this resistance increases with age.
The team collected data on How nine major areas change with age: cognitive abilities, personality traits (the so-called Big Five: openness to experience, responsibility, extraversion, agreeableness and emotional stability), emotional intelligence, financial literacy, moral reasoning, sunk cost resistance, cognitive flexibility, cognitive empathy and ‘need for cognition’ (taste for mental effort).
The data were converted to the same scale and two weighting models were compared: one ‘conventional’, which gives more weight to intelligence and personality, and another ‘broad’, which integrates applied competencies more prominently. Both place the peak at maturity, but diverge at the extremes; With the conventional approach, the elderly are below the young and with the broad approach, the elderly and the young are almost on par.
According to the study, if we look for profiles suitable for high-risk decisions (business, administration, politics), The age group with the best balance between mental speed, experience, stability and judgment would be between 40 and 65 years old.. Not because youth is of no use – it continues to excel in tasks that require rapid calculation and learning new rules – but because real performance in the professional world is rarely decided by computing speed alone. Accumulated knowledge, calm under pressure and resistance to bias are also important.
Thus, researchers conclude that the young brain is faster while the mature one is more complete. ‘Age, by itself, does not set global capacity: performance depends on how different skills that rise or fall throughout life are combined and applied with experience’they say in the study. Therefore, the maximum comes in the second half of life.