Forget everything you have been told about the brain switching off after 60. Dr Norman Swan, one of Australia’s most trusted voices on health, says the real story of ageing minds is more encouraging and far stranger than most of us assume.
In his new book The Brain Cliff, Swan sets out the science behind cognitive ageing and the everyday habits that can push that so-called cliff further down the track. Chief among his findings: daydreaming has genuine value, and retiring early may work against you.
Swan’s starting point is a simple reframe. He argues we should stop measuring our older brains against our 20-year-old selves. “One way people think about our cognitive function is by comparing it to what it was like when we were in our 20s and it’s not a valid comparison,” he said. That comparison, he said, wrongly convinces people they have slipped into deficit when the brain has simply changed, not deteriorated.
Yes, fluid intelligence – the raw speed of problem-solving – does peak in our 20s. But Swan points out that unless your daily work depends on split-second maths, that decline matters far less than what happens to crystallised intelligence: the accumulated knowledge, judgment and pattern recognition built over a lifetime. That kind of intelligence, he said, can keep improving with age.
The second surprise is what Swan calls scaffolding. As we age, he explained, the brain builds new networks of nerve connections that function much like the internal scaffolding of a skyscraper, providing structure the brain can lean on. This scaffolding first spreads across the brain, then moves into the frontal lobes and the prefrontal cortex, the region responsible for judgment, decision-making and emotional control.
The stronger that scaffolding, the further the brain cliff sits in the distance. Swan’s advice follows naturally from that: do what helps the scaffolding form, and avoid what gets in its way. Letting the mind wander, rather than filling every quiet moment with a screen, appears to be one of the habits that supports this internal architecture. Staying in meaningful work or activity beyond the traditional retirement age, rather than stepping back too soon, appears to be another.
To test these ideas in the real world, Swan sought out what he calls cognitive super-agers, and the range of them makes the point better than any statistic could. Among the people he interviewed was an illiterate 95-year-old shoemaker whose memory and judgment remained sharp, sitting alongside a woman with a career built entirely on formal learning. Different lives, different paths, the same result: brains that kept building rather than winding down.
Swan’s message is less about chasing youth than about giving the ageing brain something worth building with. The scaffolding metaphor sticks because it turns an anxious question – am I losing it? – into a practical one: what am I doing today to keep the structure standing?
As Swan sees it, the brain cliff is real, but it is not fixed. Every day spent thinking, working, wondering and staying curious moves the edge a little further away.
