As the 2024 US presidential election approaches, the advanced age of candidates Joe Biden and Donald Trump has reignited debates about whether politicians can be too old to lead. Science suggests both advantages and drawbacks to having older leaders, with cognitive function at the centre of discussions.
Biden, aged 81, and Trump, 77, are the oldest contenders ever to seek the US presidency. Their age has come under scrutiny, particularly after Biden's performance in the June 27 debate raised concerns about his stamina. Special Counsel Robert Hur previously described Biden as “an elderly man with a poor memory” in a report, which the White House dismissed as inappropriate.
Other US politicians face similar questions. Judge Pauline Newman, 96, was suspended amid an inquiry into her fitness, while senators Chuck Grassley, 90, and Bernie Sanders, 82, remain in office. Critics argue that gerontocracies fail to represent younger populations.
Neuroscience shows that cognitive performance varies widely with age. Executive function, which governs problem-solving and impulse control, declines from the 30s and accelerates after 70. White matter disease, affecting a third of people over 65, can exacerbate this decline. However, some “super agers” retain mental acuity comparable to much younger individuals.
Mark Fisher of the University of California, Irvine, suggests 65 as a general threshold for cognitive decline, given that a significant proportion over that age have executive dysfunction. Yet, life expectancy varies—73 for US men—raising questions about whether age alone is the right metric.
The debate continues as the US election highlights the tension between experience and cognitive fitness. Whether cognitive tests should be mandatory for older politicians remains a divisive issue.
