A Lifetime of Knowledge Can Benefit Memory in Old Age
As most people are aware, aging is typically associated with declines in cognitive functioning (see Harada, Natelson Love, & Triebel, 2013 for a review). This is true not only for those who develop cognitive impairments, like Alzheimer’s Disease, but also healthy older adults. Perhaps the most noticeable change is the general slowing of cognitive functioning (Salthouse, 1996). Speed of processing is reduced in older adults compared to younger adults – and this is probably not surprising to most readers. This general slowing is usually coupled with declines in specific areas of cognition, like memory.
Older adults perform worse in comparison to younger adults on a variety of memory tasks, including working, short-term, and long-term memory. (Park et al., 2002). One form of memory that is especially susceptible to decline with age is associative memory (Naveh-Benjamin, 2000). Associative memory involves remembering the linkage of two or more items, like words or images. We see this type of paired information in our daily lives – for example, faces paired with names, products paired with prices, and medications paired with side effects. Because of the prevalence of this kind of information in our daily lives, a deficit in associative memory is a common complaint amongst older people.
Working memory, short-term memory, long-term memory, and associative memory all fall under the category of episodic memory, which is generally defined as memory for events or episodes that someone has personally experienced (Tulving, 2002). A key component of episodic memory is the context of the memory. For example, if I ask you to recall what you had for breakfast this morning, you might be thinking of opening a cabinet and selecting your cereal or stopping by the coffee shop where you picked up a muffin, and you might even be remembering the smell of coffee or your internal feelings during that event. These are examples of the contextual features of your memory for eating breakfast this morning.
A different type of memory is semantic memory, which is memory for general knowledge or facts and includes memory for word meanings and language (Craik, 2000, p. 84). Contrary to episodic memory, semantic memory is not associated with the context in which it was learned. An example of semantic memory is the question, “Who was the first president of the United States?” You probably know the answer to that, but now try to remember when and where you learned that information. While older adults experience significant deficits in episodic memory, they show almost no differences in semantic memory (Park et al., 2002).
It makes sense that older adults have accumulated more semantic knowledge during their lifetimes than younger adults – they’ve lived longer, probably have more experience practicing their language skills, and may have more general knowledge about the world. The important question then becomes: can this semantic knowledge improve older adults’ ability to remember episodic information and, more specifically, associative information? Research shows that it can. In tests of word pairs, older adults were worse than young adults at remembering unrelated word pairs, but there were no age differences for related word pairs (Naveh-Benjamin, 2000). This suggests that older adults may be able to more effectively bind together pieces of information that match their existing schemas, or mental representations of concepts. For example, would you be more likely to remember a pair if you saw “dog-cat” or “dog-table?” Similarly, Worden and Sherman-Brown (1983) showed that older adults were better at remembering words from past eras (i.e., kettle, blackboard) than more modern or rare words, possibly because they are able to incorporate the older words with more extensive prior knowledge of those eras.
This ability to rely on semantic memory or prior knowledge in order to aid in remembering new episodic memories was defined by Craik and Bosman (1992) and termed schematic support. While this ability has been shown to improve associative memory in some studies, a few findings have been inconsistent. For example, Arbuckle, Cooney, Milne, & Melchior (1994) failed to find a benefit of using prior schemas for spatial memory. Additionally, overreliance on prior knowledge can lead to increased false memories (Umanath & Marsh, 2014). For example, in a well-known paradigm (Deese, 1959; Roediger & McDermott, 1995), if older adults study a list of words like, “thread, pin, knitting, thimble,” they are also more likely to recall seeing the word “needle” than younger adults, even though it was not in the list they viewed (Balota et al., 1999).
Despite some inconsistent results and potential downfalls of reliance on schematic support, there are many examples of more real-world situations in which use of this strategy is beneficial for older adults’ memory. For example, when shown images of common grocery items paired with either a market value price (i.e., matches a typical grocery price) or an over-market price (i.e., much higher than a price you would see in a grocery store), older adults were worse at recalling the prices of the over-priced items, but were just as good as younger adults at recalling the prices of the market value items (Castel, 2005). In this case, it seems older adults were able to better incorporate the market value items with their schemas, which helped them remember the prices. Other research has shown that this effect holds for tasks that involve remembering fictitious brand names – when the images of the brand logos (say, a leaf) are shown with a name that semantically matches the image (say, stem), age differences are eliminated (Mohanty, Naveh-Benjamin, & Ratneshwar, 2016).
Interestingly, there may be situations in which prior knowledge can actually protect older adults from false memories. Previous research has shown that, even if told a statement is false, simply repeating the statement (thereby making it more familiar or “fluent”) leads older adults to falsely remember that statement as true (Skurnik, Yoon, Park, & Schwarz, 2005). However, a recent study by Brashier, Umanath, Cabeza, and Marsh (2017) asked young and older adults to read repeated true and false statements and evaluate their truthfulness. They then compared the evaluations with each participant’s prior knowledge. They found that older adults were more likely to rate the false statements as true only if they did not have prior knowledge of the fact – when they did have prior knowledge, they were more accurate in correctly rating the statements as false. In fact, young adults were more likely than older adults to incorrectly rate a statement as false, even when they had prior knowledge of that statement. For example, young and older adults might have known prior to the study that the capital of Peru is Lima, but when they saw the repeated statement, “The capital of Peru is Buenos Aires,” older adults were more likely to use their prior knowledge to rate this statement as false, while younger adults were more likely to be swayed a sense of fluency or familiarity and therefore incorrectly rate the statement as true.
In summary, although older adults have general declines in memory ability, especially for associative information, the use of prior knowledge (schematic support) can be an effective strategy in reducing memory errors and maintaining the ability to remember everyday information. This strategy may even contribute to the idea that people become wiser with age; older adults generally have more knowledge of the world and may, in some situations, be better evaluators of information because of their prior knowledge. In a more practical sense, this knowledge can be important for improving the way copious amounts of information are presented to older adults. Perhaps future research should focus on the best ways to incorporate new information into older adults’ existing schemas and/or routines.
Arbuckle, T. Y., Cooney, R., Milne, J., & Melchior, A. (1994). Memory for spatial layouts in relation to age and schema typicality. Psychology and Aging, 9, 467–480.
Balota, D. A., Cortese, M. J., Duchek, J. M., Adams, D., Roediger, H. L., III, McDermott, K. B., & Yerys, B. E. (1999). Veridical and false memories in healthy older adults and in dementia of the Alzheimer’s type. Cognitive Neuropsychology, 16, 361–384.
Brashier, N. M., Umanath, S., Cabeza, R., & Marsh, E. J. (2017) Competing cues: Older adults rely on knowledge in the face of fluency. Psychology and Aging, 32(4), 331–337.
Castel, A. D. (2005). Memory for grocery prices in younger and older adults: The role of schematic support. Pyschology and Aging, 20(4), 718–721.
Craik, F. I. M. (2000). Age-related changes in human memory. In D. C. Park & N. Schwarz (Eds.), Cognitive aging: A primer (pp. 75–92). Philadelphia, PA: Psychology Press.
Craik, F. I. M., & Bosman, B. A. (1992). Age-related changes in memory and learning. In H. Bouma & J. A. M. Graafmans (Eds.), Gerontechnology (pp. 79–92). Amsterdam: IOS Press.
Deese, J. (1959). On the prediction of occurrence of particular verbal intrusions in immediate recall. Journal of Experimental Psychology, 58, 17–22.
Harada, C. N., Natelson Love, M. C., & Trielbel, K. L. (2013). Normal cognitive aging. Clinical Geriatric Medicine, 29(4), 737–752.
Naveh-Benjamin, M. (2000). Adult age differences in memory performance: Tests of an associative deficit hypothesis. Journal of Experimental Psychology: Learning, Memory, and Cognition, 26, 1170–1187.
Mohanty, P., Naveh-Benjamin, M., & Ratneshwar, S. (2016). Beneficial effects of semantic memory support on older adults’ episodic memory: Differential patterns of support of item and associative memory. Psychology and Aging, 31(1), 25–36.
Park, D. C., Lautenschlager, G., Hedden, T., Davidson, N. S., Smith, A. D., & Smith, P. K. (2002). Models of visuospatial and verbal memory across the adult life span. Psychology and Aging, 17, 299–320
Roediger, H. L., III, & McDermott, K. B. (1995). Creating false memories: Remembering words not presented in lists. Journal of Experimental Psychology: Learning, Memory, and Cognition, 21, 803–814.
Salthouse, T. A. (1996). The processing-speed theory of adult age differences in cognition. Psychological Review, 103, 403–428.
Skurnik, I., Yoon, C., Park, D. C., & Schwarz, N. (2005). How warnings about false claims become recommendations. Journal of Consumer Research, 31, 713–724.
Tulving, E. (2002). Episodic memory: From mind to brain. Annual Review of Psychology, 53(1), 1–25.
Umanath, S., & Marsh, E. J. (2014). Understanding how prior knowledge influences memory in older adults. Perspectives on Psychological Science, 9, 408–426.
Worden, P. E., & Sherman-Brown, S. (1983). A word-frequency cohort effect in young versus elderly adults’ memory for words. Developmental Psychology, 19, 521–530.