Retirement Life
9 August 2022

How do our thinking skills change as we get older?

The timing and degree of change we all experience in our thinking skills varies between each of us. There is certainly no one-size-fits-all. Research suggests there is a range of factors that determine our ageing trajectories. After all, we are all exposed to different lifestyle factors – some that might protect, and some that might harm our cognitive health.


To understand a bit more, we often group our thinking skills into two categories. Those which are fluid develop quickly when we are young, peak in our 20s and then slowly decline. Examples of fluid thinking skills include our speed of processing information (think about how we react to holding a hot pan, for instance) and other tasks that have a time-limited component. The second category is crystallised thinking skills – they develop slower and peak later in life. For example, our word knowledge or other processes that have become rote would be considered crystallised.


Professor Alan Gow from Heriot-Watt University in the UK, and founder of The Ageing Lab, has been researching cognitive decline and lifestyle interventions for many years.


“Our early education, our occupation and work environment, social factors and various other lifestyles and behaviours all play a role in how our cognitive skills develop or change over time,” he says. “For example, whether we smoke or we’ve experienced a brain injury in our lives have been shown to be significant factors in negatively impacting our thinking skills as we age.”

It’s a question of risk factors (like smoking and brain injuries) and protective factors (such as keeping physically fit and being socially engaged). Alan gives the analogy of a balloon. “Imagine a balloon is blown up to a given size. Over time, the air might gradually escape from the balloon – similarly, our thinking skills develop across our lifespan and might show some declines later. So how do we maintain a well-filled balloon? Well, we might get more air into the balloon to begin with – that’d be the various things we might do throughout our lives to build our mental capacities – or we might consider things to top up the air later.”


To illustrate how lifestyle might affect brain health at different points, Alan uses a study he worked on with colleagues at the University of Edinburgh. In the study, the team looked at physical activity and mental activity across our lifespan and how they were associated with thinking skills. They found that mental engagement during midlife was important for building that level of capacity (i.e. blowing the balloon up bigger). In terms of seeing less decline in older age, it seemed to be physical activity that was more important.


In addition, physically active members of the study had less brain shrinkage, higher volumes of grey matter and less damage to their white matter – all features of brain structure that are associated with better thinking skills in later life.

But what about now? Good news: there is much evidence that we still experience plasticity in the brain as we age, i.e. change is always possible.


“My general advice would be that if you smoke, stopping would be good, as well as staying physically active,” says Alan. “This includes stretching and toning to improve muscle tone. It’s also important to keep socially active. It’s not necessarily the quantity but the quality of the relationships which are important. And taking up something challenging and fun, new or novel to build brain capacity is going to be helpful,” says Alan.


So to put it in a nutshell, it is likely that positive and proactive lifestyle changes at any age (no matter how early or late they are started) can be worthwhile for positive brain health and dementia prevention.


Alan summarises this general advice with an important caveat, saying if people are genuinely worried about changes they are experiencing with their thinking skills, they should speak to their GP or specialist.

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Written by:

Kathy Catton

Kathy Catton is a freelance writer and editor, based on the Banks Peninsula. She is an experienced feature writer, magazine editor and copywriter. Quick to grasp the crux of any story and tell it in plain English, Kathy enjoys bringing stories to readers that surprise and delight.

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