As we hit midlife, our brains aren’t quite the same as they used to be. But does this mean that our brains don’t work as well as before? Yes and no.
How do we observe our environment? How do we remember and access the information that we’ve previously stored? How does our brain handle the information it receives? What are the aspects that affect our ability to learn? How does ageing change our brains and our cognitive abilities?
Cognitive functions is a complex and interconnected system
Cognitive brain functions make it possible for us humans to work with information in a meaningful way. It’s a highly complex and interconnected system serving numerous intellectual processes, such as attention, memory, reasoning and decision-making.
We are told that as we age, we start frequently losing our belongings, forgetting names and appointments and losing the ability to learn anything new and complicated, such as modern technology. Not quite.
Whereas it’s true that our brains change as we age, our ability to think, reason and learn does not decline at all as drastically as we might think. The biggest changes concern our memory—and we’ll get back to that a little later.
Physiological changes of the brain and our senses
You’ve probably noticed it already: You can’t see quite as well as you used to, and also your hearing might not be as crisp as it was before. (Or perhaps it’s just that crickets really have disappeared from the planet?)
In addition, your brain—literally—shrinks in volume and declines in weight at a rate of around 5% per decade after age 40. The prefrontal cortex is affected most and the changes start occurring well before older adulthood.
Also, the falling levels of dopamine, serotonin as well as sex hormones, have been associated with declining cognitive performance. Various age-related illnesses, such as diabetes and cardiovascular disease, start to take their toll among some of us, too.
We all become slower
No, it’s not that our teenage children or young co-workers are spectacularly fast—it’s us. We slow as we age.
A widely accepted general slowing hypothesis states that the slowing is not task-dependent and that it is the primary contributor to the declines in cognitive functioning associated with ageing.
Episodic memory, the “memory of events”, declines first
If we didn’t have the ability to store and retrieve memories, it would probably be very difficult if not impossible to try to lead a normal, meaningful life.
Our working memory helps us run our daily lives—a phone number, for instance, stays in our mind for as long as it takes us to dial it.
Long-term memory is, as its name implies, storage for everything that we will remember for a long time. In this storage, we can find all our skills as well as concepts that we’ve learned and events that we’ve experienced. This autobiographical memory of events is called episodic memory.
It’s known that the performance on episodic and working memory tasks declines with age. However, there are noticeable differences between individuals so that some are affected as early as in their 50s, but others get to enjoy relatively preserved memory functioning well into their 70s.
Benefits of life-long learning
Ageing affects our learning, but it’s not all bad news. Even though we become poorer at remembering details, we, on the other hand, become better at managing larger chunks of information. It’s good to remember again, though, that there are big individual differences.
Our problem solving and decision-making abilities remain pretty good, and they can in some ways even improve: Due to our accumulated knowledge and life experiences, we are more flexible and understand that problems often have more than one solution.
By midlife, we know that it’s important to look after our physical health. We walk and jog, we go to the gym and take yoga classes. Our brains need exercise, too. As Dr Ipsit Vahia, director of geriatric outpatient services for McLean Hospital explains in Harvard Health Blog, the process of learning can stimulate new brain cell growth even late into adulthood.
From wit to wisdom
What do we know about intelligence in general? Does ageing make us all scatty? Not necessarily, but the nature of our intelligence does change.
Conventional IQ tests are designed to measure so-called fluid intelligence, that is, our wit, the flexibility of thought and the ability to solve puzzles.
Crystallized intelligence, on the other hand, is based on an individual’s past experiences and accumulated knowledge.
As our fluid intelligence decreases with age, the opposite is true with crystallized intelligence: We may not be as witty as we were—but we become wiser.
Changes to be expected in midlife
Changes in our cognitive abilities in normal ageing are rarely abrupt. During midlife years, we probably start to notice a few subtle changes: We might not be able to recall all the names of our high school classmates anymore, or occasionally forget where we placed our reading glasses (might be on your head!).
All in all, adult cognitive development is a complex process that may be even more active than cognitive development during childhood
Don’t get stuck on stereotypes
It’s important to give negative stereotypes about ageing as little attention as they deserve—that is, not at all. If you fear that you might fall over, you are more likely to do so. If you believe that your cognitive ability and performance is not up to par, you are likely to start acting according to your own beliefs, creating a self-fulfilling prophecy.
The bottom line, when it comes to age-related cognitive decline, is that ageing does not affect our memory and ability to learn at all as drastically as is commonly assumed. A human brain is a fantastically adaptable organ that flexibly adjusts to many changes both within and outside our bodies.