An active brain as you age could make all the difference

The research is clear – maintaining an active brain is one of the most important elements of flourishing in later life, though it’s sometimes underestimated. It’s useful for its own sake to keep your brain busy, agile and curious, of course; and it is also closely tied to independence, resilience, and even reduced risk of dementia and earlier death.

Aging is not a disease – it’s a natural process. And part of that process involves changes to the brain. Certain regions that support learning, memory, and complex decision‑making gradually shrink as we age, and the connections between brain cells can become less efficient.

But this is only part of the story.

Other aspects of cognition – like vocabulary, accumulated knowledge, and emotional understanding – often stay steady or even improve. This is sometimes described as the difference between fluid intelligence (the ability to process new information very quickly, and which starts dropping before you turn 30) and  crystallised intelligence (accumulated learning, life experience and word skills, which generally increase over life, as fluid intelligence drops off). Recent research shows a complex interweaving of these two attributes over life, and I am sure there will be further findings.

Most important of all, the brain maintains its ability to adapt to changes, develop connections and find new pathways around damaged areas. This adaptive plasticity is a big part of why mental activity, new learning, and taking on challenges remain so important throughout life.

One of the most useful ideas to emerge from brain‑ageing research is ‘cognitive reserve’. It is the reason why, although some change is inevitable, the way we live can influence how those changes show up in daily life.

Cognitive reserve acts as a kind of resilience fund for the brain. Two people might have similar levels of age‑related change or even early Alzheimer’s pathology, yet one still functions well in everyday life while the other experiences obvious impairment. The difference often lies in how much reserve they have built over the years.

A few things in particular contribute to this reserve:

• Time spent in education and intellectually demanding work  
• Lifelong learning – doing courses or self-learning, reading deeply and widely or engaging in hobbies to a level beyond dabbling (which sadly means my weekend pottery attempts definitely do not count…)  
• Rich social networks and stimulating conversations  
• Engaging in mentally complex leisure activities

These experiences seem to help the brain develop alternative pathways and strategies it can draw on as life goes on – and the more varied and sustained the mental activities, the larger this resilience bank appears to be. Many people think brain training games like Sudoku or crosswords are enough, but unfortunately once you master the rules, it’s not building new connections. I love Wordle and do it every day but it’s not adding to brain reserves. It is very satisfying to do and share, and worthwhile to do, just not in this context. 

It is also becoming clearer that these brain advantages are not the result solely of mind activity but rely on the way learning, social support and broader health behaviours intertwine over decades. Curiosity is also featuring in this growing body of research. 

We probably all know people whose lives become smaller as they age, and for whom curiosity is not a common attribute. But if you can retain your sense of curiosity about life, you’ll be more likely to explore, ask questions, and seek out new experiences. That ongoing impulse toward these things keeps us engaging with complex environments – learning new technology, navigating unfamiliar places, joining new groups, or digging into topics we’ve never studied before.

I have written here already about the importance of fun and creative adventures, which both rely heavily on curiosity and a willingness to play. And serious studies are starting to show that:

• Higher levels of curiosity in later life are linked to better performance on demanding problem‑solving tasks 
• Certain kinds of curiosity – especially interest in information that’s personally meaningful – can remain strong and even increase  
• A loss of curiosity may be an early sign of cognitive decline, especially when coupled with memory or behavioural changes

So, it’s clear an active brain is a very good thing, but what is the right amount of challenge for your brain?

Not all mental activity is created equal. When you focus on a demanding task (not something easy or which you have done many times, like Wordle or Sudoku) your brain is likely to use additional regions to help out. This is a key factor in maintaining performance in the face of the changes that come with age.

Researchers talk about tasks that are:

• Novel – something you haven’t mastered yet  
• Effortful – they require thinking, focus, and occasional struggle, even frustration  
• Achievable – you need to work hard, but you see improvement with practice, rather than feeling chronically overwhelmed

Examples include traveling to new places, learning a new language, taking up a musical instrument later in life, mastering photo editing tools, responding thoughtfully to complex reading. It should be something you really want to do and and enjoy, that stretches you without exhaustion or chronic stress. Book club could qualify, provided it’s the ‘let’s all read the book and actually discuss it’ type, rather than the ‘let’s all drink and gossip’ type. There’s nothing wrong with the latter, but it’s not building brain reserves.

And as we know from reading the many wellbeing articles around now, an active brain is part of a cluster of ageing behaviours that together reduce the risk of many chronic or life-threatening conditions. A healthy diet, exercise, less alcohol and no smoking are all part of this, along with cardiovascular health, good sleep and minimising stress. I would also add ‘having fun’ to this list, as your brain needs stimulation but it also needs time off…

It’s easy for conversations about brain aging to slip into anxiety and avoidance. Many people fear dementia, feel haunted by stories of decline, and quietly worry whether forgetting names is the beginning of the end. In fact, while the total number of people with demential in Australia is rising, the number of cases per 1000 Australians is falling – it has dropped 20-25% in the last decade and the trend is continuing. 

I will be writing more about these data trends and the reasons for them soon, but in the meantime it is very helpful to reframe your natural concerns. Instead of ‘(How) can I avoid decline?’, it’s more useful to ask, ‘How can I build my cognitive reserve in ways that support a meaningful and engaged life?’

Maintaining an active brain as we age is not about clinging desperately to youth or denying the changes that time brings. It’s about using tools like curiosity, challenge, learning, social engagement and physical health to support a later life that is rich in purpose, satisfaction, and joy.

I’m signing up for some lectures at the art gallery; what might you do to enrich your life?