Memory is not just one thing–it is a collection of abilities that allows us to change our behavior in response to previous experiences. The timescale of memory includes information from what just happened a second ago to events that occurred decades ago. Research on the cognitive and biological underpinnings of memory reveals that there is not just one memory system in the brain, rather there are many specialized systems that give us the ability to hold information in mind while it’s needed (working memory), the ability to learn new skills or habits (non-declarative or implicit memory), and the ability to learn new facts and events (declarative or explicit memory).
The number one cognitive complaint in healthy older adults is a decrease in memory ability, usually in our ability to remember events (known as episodic memory). Some memory changes are normal and to be expected. It seems that as we get older we rely less on memory for specific details and more on the general gist of what happened. There may be structural changes happening in the brain that support this change.
Dementias are cognitive disorders associated with age characterized by memory impairment and impairment in at least one other cognitive domain that impairs social or occupational functioning characterized by a gradual onset and continual decline. Alzheimer’s disease (AD) is the most common form of dementia, accounting for about 62% of cases. The number one risk factor for AD is age.
Are there things you can do to reduce your risk of AD and other dementias? The best evidence suggests staying active physically, mentally, and socially. All these domains are associated with lower risk of developing AD.
Below are resources on memory, aging, and dementia in case you would like to learn more.
Memory References
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