§ Claim under review · Study
"A University of Melbourne study found that the human brain reaches peak cognitive performance (combining working memory, attention, decision-making, and emotional stability) between the ages of 55 and 60"
Verdict
Partially accurate but misleading
Confidence
HighSummary
This post is based on a real study, but it names the wrong university and reframes the finding in a way that changes its meaning. The research was published in the journal Intelligence in 2025 by Gilles Gignac of the University of Western Australia and Marcin Zajenkowski of the University of Warsaw. It was not a University of Melbourne study, and the Euronews article the post itself links names the correct university. The 55 to 60 figure is genuine, but it does not come from brain scans or a measure of raw mental horsepower. The researchers combined previously published data on 16 psychological traits into a single weighted index, and the late peak is driven largely by things like accumulated knowledge, financial literacy, moral reasoning and emotional stability, while reasoning speed and memory still decline from early adulthood. The post's claims about the prefrontal cortex and neural pathways are not findings of this study. The post also uses the science as a hook to promote a brain supplement guide, and the research says nothing about supplements.
The readings
key figures from the evidencecognitive and personality-related dimensions reviewed in study
sample size for emotional intelligence data used in index
Why this verdict
Evidence
A real, peer-reviewed study underlies this post, and the "55 to 60" figure is genuine. But the institution named in the claim is wrong. The study was authored by Gilles E. Gignac of the University of Western Australia and Marcin Zajenkowski of the University of Warsaw.
The University of Western Australia's own newsroom states that the article by Associate Professor Gilles Gignac, from UWA's School of Psychological Science, originally appeared in The Conversation on 15 October 2025, reporting that psychological functioning peaks between ages 55 and 60.
The University of Melbourne is not involved. Notably, the Euronews article that the post itself links identifies Gignac as "co-author of the study and professor of psychology at the University of Western Australia." The post contradicts its own cited source.
On the substance of the finding: the paper's own highlights state that age trends were reviewed across 16 key cognitive and personality-related dimensions, that age trajectories varied widely with some traits declining and others improving, that a weighted composite index was developed from theory and evidence, and that overall cognitive-personality functioning peaks between ages 55 and 60.
Gignac wrote that overall mental functioning peaked between ages 55 and 60 before beginning to decline from around 65, and that the decline became more pronounced after age 75.
METHODOLOGY AND CONTEXT
This is not a brain study. No brain imaging, no new participants, no neuroscience measurement. It is a quantitative synthesis of previously published age trajectories. The researchers constructed a Cognitive-Personality Functioning Index (CPFI) and compared two weighting approaches: a Conventional model emphasizing intelligence and core personality traits, and a Comprehensive model integrating a broader array of dimensions. Both models revealed a peak in overall functioning during late midlife, ages 55 to 60, but diverged at the younger and older ends of adulthood.
What was actually measured. The scholars analyzed success-related cognitive and personality traits such as emotional intelligence, financial literacy, moral reasoning, resistance to sunk-cost bias, cognitive flexibility and cognitive empathy, then weighted the traits according to their importance for real-world functioning to create the Cognitive-Personality Functioning Index.
The 16 characteristics included cognitive abilities such as reasoning and memory, along with the big five personality traits: openness, conscientiousness, extraversion, agreeableness, and neuroticism.
Data sources vary widely in size and quality. Intelligence data were obtained from Salthouse (2019), with the cross-sectional data used for the present analysis rather than longitudinal data.
Emotional intelligence was modelled using open-access data from Gignac and Schlegel (2025), comprising adult participants aged 20 to 72, N = 456.
The sunk cost fallacy resistance sample included 130 adults across three age groups. Values at the extremes of the age range were extrapolated rather than observed. To estimate scores for age 18, which fell outside the observed age range, generalized additive models were fitted to LOESS-smoothed data and used to extrapolate plausible values.
Stated limitations. The technique compares different people of different ages at the same moment in time, which can confuse the effects of natural aging with generational differences, unlike longitudinal data tracking the same people over decades. The original datasets were drawn largely from Western, industrialized populations, and age-related changes in personality and cognition can differ across environments.
Findings
✓ What's accurate 6
- A real peer-reviewed study exists, published in the journal *Intelligence* (2025, vol. 113, article 101961).
- The 55 to 60 age range is accurately reported and is the study's headline conclusion.
- The reported decline starting around age 65 is accurate to the author's own description.
- The caption's point that some traits peak later is supported: conscientiousness peaked at 65 and emotional stability at 75.
- Emotional stability genuinely was one of the dimensions analyzed (as the reverse of neuroticism in the big five).
- The post does link to a real Euronews article that covers the real study.
? What's uncertain 5
- Whether the Melbourne attribution was careless error or deliberate fabrication cannot be determined from available evidence.
- I could not retrieve the full text of the paper behind the ScienceDirect paywall, so the complete list of all 16 dimensions and their individual weights is based on highlights, abstract, excerpted sections, and secondary reporting rather than full-text reading.
- The exact effect sizes and confidence intervals around the 55-60 peak estimate were not available in retrieved excerpts, so how sharp or how flat that peak is remains unclear.
- Independent replication of the CPFI approach was not found. This is a single recent paper, not a settled body of evidence.
- The post's final-paragraph claims about short-term memory and mental flexibility after 65 are directionally consistent with the paper but were not traced to specific stated figures.
Sources
6 of 6 linked to records**Gignac, G. E., & Zajenkowski, M. (2025). "Humans peak in midlife: A combined cognitive and personality trait perspective." *Intelligence*, 113, 101961**
**University of Western Australia newsroom republication of The Conversation article**
**The Conversation, Gilles E. Gignac, 15 Oct 2025**
**Euronews Health, 26 Oct 2025 (the article the post itself links)**
**PsyPost coverage**
**Stanford Center on Longevity commentary**