Memory is our life story, our solace, our joy. The thought of losing memory is also our biggest fear. There is a normal pattern of brain changes that occur as we age that can impact memory. The brain peaks in our early 20s and slowly declines for the rest of our life. It isn’t until we reach age 40 that we start noticing the effects of this decline. There are subtle changes in our ability to remember new names or do more than one thing at a time (cognitive flexibility) as the result of the cortex starting to shrink.
Physiological Changes:
· Neurons can shrink and atrophy becoming less efficient as you age
· There is a large reduction in the extensiveness of connections among neurons; these connections between cells change as you learn and can be strengthened through repeated use
· As you age these synapses (connections between neurons) falter, resulting in sporadic hiccups when trying to retrieve memory
· The hippocampus (center for new learning and memory) loses 5% of its neurons each passing decade; resulting in a total loss of 20% of neurons by the time you reach your 80s
· Aging causes major cell loss in the frontal cortex of the brain that leads to a drop in acetylcholine production; Acetylcholine is the neurotransmitter vital to learning and memory
· Older people many times experience decreased blood flow to the brain which can lead to changes in cognitive skills.
Brain Function Changes:
· The drop in blood flow to the frontal cortex is manifested in the experience of declining verbal fluency – or having trouble finding the words you want
· We have to work harder at executive function – the ability to plan and organize our activities
· Areas most affected include:
o The parietal cortex which affects construction and follow-through of vasomotor performance (think of your golf swing)
o The medial temporal lobe – affects the ability to make new long-term memories and think flexibly.
How These Changes Pertain to Memory
Now how do all of these changes pertain to memory? There are some consistent changes in types of memory through the years. “Episodic (what did I have for breakfast?), source (where did I learn about that new car?), and flashbulb (where were you on Sept.11, 2001?) memory decline the most. Semantic (words, facts, and concepts) and procedural (it’s like riding a bicycle – you never forget) memory decline the least.” (American Psychological Association). However the brain has no storage capacity issues. Changes in memory seem to center around how people encode and retrieve information. The older brain is more vulnerable to distraction. In many instances the memory was never formed because the information didn’t come in as a strong, clear signal.
Physical Risk Factors
There are some physical risk factors that contribute to memory challenges as we get older. Cerebrovascular or cardiovascular risk factors may complicate the relationship between chronological aging and the neurobiological changes that occur in cognitive aging. Increased blood pressure is associated with reduced speed of processing, visuoconstruction ability, learning, memory and executive function. Insulin resistance and diabetes are affiliated with diminished cognitive abilities in later life. Hyperlipidemia (e.g. high cholesterol) poses as a potential cerebrovascular risk factor that negatively impacts cognition in older adults.
Cognitive Reserve
If we are lucky and have been living a healthy brain lifestyle, we have built up cognitive reserve. We draw on brain resilience to actively cope with brain pathology or negative changes by using the existing approaches or recruiting other available brain networks to get the job done. Cognitive reserve may moderate the relationship between normal brain aging changes and the cognitive outcomes.
When Memory Loss Is a Sign of Dementia
Memory lapses that have little impact on daily performance and the ability to do what you want to do are troublesome but not signs of dementia.
Dementia on the other hand, is marked by an unrelenting, disabling decline in two or more intellectual abilities, such as, language, judgment and abstract thinking.
When your memory loss is so severe that it disrupts your work, hobbies, social activities and family relationships – you may be exhibiting signs of Alzheimer’s disease. This type of memory loss deserves your attention and a trip to the doctor.
Tips for Maintaining and Improving Your Memory:
Throughout all these articles I have noted the ability of the brain to change to the environment. Even though brain aging changes are normal aging processes, we can work to reverse the process. Here are some tips for maintaining and improving your memory:
· Socialize: participate in social and community activities
· Get moving: physical activity and exercise can boost and maintain brain function
· Train your brain: Learn tools and strategies to help you remember names, what you read and see
· Don’t buy into ageist stereotypes about memory decline: Having positive beliefs about aging can improve memory performance
· It’s difficult to gain knowledge if you can’t see or hear well: Wear your glasses and hearing aids; have your eyes and ears tested regularly
· Keep a sense of control and confidence in your memory: Don’t assume that little memory lapses mean you have dementia
· Avoid distractions that divert your attention: Distractions can range from trying to multitask to loud noises. Your thoughts can even be distractions. Pay attention.
(American Psychological Association)
References:
Adelson,R. (September, 2005). Memory changes in older adults. Retrieved September 5, 2016 from http://www.apa.org/research/action/memory-changes.aspx
American Psychological Association. Memory and Aging. Retrieved September 5, 2016 from http://www.apa.org/pi/aging/memory-and-aging.pdf
Brinkman,A.M. & Stern, Y. Aging and memory in humans. Encyclopedia of Neuroscience (2009) vol 1 pp 175-180. Retrieved September 5, 2016 from http://www.cumc.columbia.edu/dept/…agingandmemoryinhumans.pdf
HelpGuide.org. Age-Related Memory Loss. Retrieved May 23, 2018 from https://www.helpguide.org/articles/alzheimers-dementia-aging/age-related-memory-loss.htm
Mohs,R.C. How human memory works. Retrieved September 4, 2016 from http://science.howstuffworks.com/life/inside-the-mind/human-brain/human-memory.htm
