Gilles E. Gignac, Associate Professor of Psychology, The University of Western Australia
As your youth fades further into the past, you may start to fear growing older.
But research my colleague and I have recently published in the journal Intelligence shows there’s also very good reason to be excited: for many of us, overall psychological functioning actually peaks between ages 55 and 60.
And knowing this highlights why people in this age range may be at their best for complex problem-solving and leadership in the workforce.
Different types of peaks
There’s plenty of research showing humans reach their physical peak in their mid-twenties to early thirties.
A large body of research also shows that people’s raw intellectual abilities – that is, their capacity to reason, remember and process information quickly – typically starts to decline from the mid-twenties onwards.
This pattern is reflected in the real world. Athletes tend to reach their career peak before 30. Mathematicians often make their most significant contributions by their mid-thirties. Chess champions are rarely at the top of their game after 40.
Yet when we look beyond raw processing power, a different picture emerges.
From reasoning to emotional stability
In our study, we focused on well-established psychological traits beyond reasoning ability that can be measured accurately, represent enduring characteristics rather than temporary states, have well-documented age trajectories, and are known to predict real-world performance.
Our search identified 16 psychological dimensions that met these criteria.
These included core cognitive abilities such as reasoning, memory span, processing speed, knowledge and emotional intelligence. They also included the so-called “big five” personality traits – extraversion, emotional stability, conscientiousness, openness to experience, and agreeableness.
We compiled existing large-scale studies examining the 16 dimensions we identified. By standardising these studies to a common scale, we were able to make direct comparisons and map how each trait evolves across the lifespan.
Peaking later in life
Several of the traits we measured reach their peak much later in life. For example, conscientiousness peaked around age 65. Emotional stability peaked around age 75.
Less commonly discussed dimensions, such as moral reasoning, also appear to peak in older adulthood. And the capacity to resist cognitive biases – mental shortcuts that can lead us to make irrational or less accurate decisions – may continue improving well into the 70s and even 80s.
When we combined the age-related trajectories of all 16 dimensions into a theoretically and empirically informed weighted index, a striking pattern emerged.
Overall mental functioning peaked between ages 55 and 60, before beginning to decline from around 65. That decline became more pronounced after age 75, suggesting that later-life reductions in functioning can accelerate once they begin.
Getting rid of age-based assumptions
Our findings may help explain why many of the most demanding leadership roles in business, politics, and public life are often held by people in their fifties and early sixties. So while several abilities decline with age, they’re balanced by growth in other important traits. Combined, these strengths support better judgement and more measured decision-making – qualities that are crucial at the top.
Despite our findings, older workers face greater challenges re-entering the workforce after job losses. To some degree, structural factors may shape hiring decisions. For example, employers may see hiring someone in their mid-fifties as a short-term investment if retirement at 60 is likely.
In other cases, some roles have mandatory retirement ages. For example, International Civil Aviation Organisation sets a global retirement age of 65 for international airline pilots. Many countries also require air traffic controllers to retire between 56 and 60. Because these jobs demand high levels of memory and attention, such age limits are often considered justifiable.
However, people’s experiences vary.
Research has found that while some adults show declines in reasoning speed and memory, others also maintain these abilities well into later life.
Age alone, then, doesn’t determine overall cognitive functioning. So evaluations and assessments should focus on individuals’ actual abilities and traits rather than age-based assumptions.
A peak, not a countdown
Taken together, these findings highlight the need for more age-inclusive hiring and retention practices, recognising that many people bring valuable strengths to their work in midlife.
Charles Darwin published On the Origin of Species at 50. Ludwig van Beethoven, at 53 and profoundly deaf, premiered his Ninth Symphony. In more recent times, Lisa Su, now 55, led computer company Advanced Micro Devices through one of the most dramatic technical turnarounds in the industry.
History is full of people who reached their greatest breakthroughs well past what society often labels as “peak age”. Perhaps it’s time we stopped treating midlife as a countdown and started recognising it as a peak.
Gilles E. Gignac does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.
