This blog is based on an article by Alexis Wnuk, published in BrainFacts.org, entitled “How the Brain Changes With Age”.
Our bodies change in noticeable ways as we age
Our bodies change in noticeable ways as we age. Our hair grays, our skin wrinkles and loses its elasticity. Less obvious are the changes happening in our brains.
Just like muscles and joints, certain cells in our brains can stiffen up too, as evidenced in a recent study in rats. This is just one of many ways our brains change as we age – starting with declines in memory and cognitive abilities, all the way to microscopic changes to brain cells and chemistry.
The normal aging process brings subtle changes in cognitive abilities. Committing new information to memory and recalling names and numbers now takes longer. Autobiographical memory of life events and accumulated knowledge of learned facts and information – both types of declarative memory – decline with age, while procedural memories like remembering how to ride a bike or tie a shoelace remain largely intact.
Working memory is the ability to hold a piece of information in mind, such as a phone number, password, or the location of a parked car — also declines with age. Some studies suggest a slow decline starts as early as age 30. Working memory depends on the rapid processing of new information rather than stored knowledge. Other aspects of this kind of fluid intelligence (such as processing speed and problem-solving), also decrease with age.
Certain aspects of attention (such as divided attention) can become more difficult as our brains age.
We might have a harder time focusing on what our friends are saying in a noisy restaurant. Splitting our focus between two tasks – like holding a conversation while driving – also becomes more challenging with age.
But it’s not all downhill after age 30
In fact, certain cognitive abilities improve in middle age.
In the Seattle Longitudinal Study, which tracked the cognitive abilities of thousands of adults over the past 50 years,*people performed better on tests of verbal abilities, spatial reasoning, math, and abstract reasoning in middle age than they did when they were young adults.
You can teach an old dog new tricks
Contrary to the adage that you can’t teach an old dog new tricks, there is growing evidence that we can and do learn throughout our lives. *Neuroscientists are learning that our brains remain relatively “plastic” as we age, meaning that they’re able to reroute neural connections to adapt to new challenges and tasks.
Structural Changes in the Brain’s Structure and Chemistry
These alterations in cognitive ability reflect changes in the brain’s structure and chemistry. As we enter midlife, our brains change in subtle but measurable ways. The overall volume of the brain begins to shrink when we’re in our 30s or 40s, and the rate of shrinkage increases around age 60.
But, the volume loss isn’t uniform throughout the brain — some areas shrink more, and faster, than other areas. The prefrontal cortex, cerebellum, and hippocampus show the biggest losses, which worsen with advancing age. Our cerebral cortex, the wrinkled outer layer of the brain containing neuron cell bodies, also thins as we age. Cortical thinning follows a pattern similar to volume loss and is especially pronounced in the frontal lobes and of the temporal lobes.
The “last in, first out” theory of brain aging
According to a new theory among brain scientists, the areas of the brain that experience the most dramatic changes with age are also among the last to mature in adolescence. This has led scientists to propose a “last in, first out” theory of brain aging – the last parts of the brain to develop are the first to deteriorate.
Changes at the level of individual neurons contribute to the shrinkage and cortical thinning of the aging brain. Neurons shrink and retract their dendrites, and the fatty myelin that wraps around axons deteriorates. The number of connections, or synapses, between brain cells also drops, which can affect learning and memory.
Strategies to boost neurogenesis, such as regular exercise, can improve cognitive function
The formation of new neurons — a process called neurogenesis — also declines with age. Although scientists once thought neurogenesis came to a halt after birth, we now know that two brain regions continue to add new neurons throughout life: the olfactory bulbs and the dentate gyrus of the hippocampus. Although the jury is still out on these findings, recent studies with mice have found that strategies to boost neurogenesis, such as regular exercise, can improve cognitive function.
Manipulating serotonin levels might help prevent and treat memory loss
As we age, our brains may also generate fewer chemical messengers
Several studies have reported that older brains synthesize less dopamine, and there are fewer receptors to bind the neurotransmitter. One study found 60- and 70-year-olds with mild cognitive impairment had less serotonin in their brains, and the researchers are wondering whether manipulating serotonin levels might help prevent and treat memory loss. See also “7 Foods That Could Boost Your Serotonin: The Serotonin Diet”.
Adopting a Healthy Lifestyle
Our brains undergo myriad changes during the aging process. However, scientists are learning every day how adopting a Adopt a Healthy Lifestyle for Low Stress Living (verywellmind.com) can delay or minimize the negative consequences of these changes.
We hope you’ve enjoyed our blog on “How the Brain Changes With Age” and that you’ll want to read up on it. Please leave us a comment on the website if you enjoyed this blog!
= = = > Click here to read another article published in Medical News Today: What Happens to the Brain As We Age> = = =
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