Memory problems in the elderly could be the result of a disorder
There is a paradox in the science of memory: empirical evidence and life experience suggest that older adults have more knowledge of the world. However, in laboratory environments, they generally perform worse on memory tests than younger adults. What can explain the disparity?
The answer could be “clutter,” according to a review of memory studies published in the journal Trends in Cognitive Science.
Tarek Amer is a postdoctoral fellow at Columbia and Harvard universities and the first author of the review. While some scientists think that as adults get older, they begin to form “impoverished memories,” memories that contain less information about the memories of younger ones, Amer and his colleagues have a different view. In contrast, “older adults may be forming too many associations between information,” Amer said.
Compared to young adults, healthy older adults (defined in the document as 60 to 85 years old) process and store too much information, probably due to the greater difficulty in deleting irrelevant information, according to the analysis. This difficulty is described as “reduced cognitive control” and may explain the disordered nature of older people’s memory representations.
“It’s not that older adults don’t have enough space to store information,” Amer said. “There is too much information that interferes with what they are trying to remember.”
This explanation comes from and is supported by the team’s review of several behavioral and neuroimaging studies. His article “makes a compelling case that as we age, part of the problem is that we become less selective,” said Charan Ranganath, a professor at the University of California, Davis Center for Neurocience. Ranganath was not part of the new newspaper.
It is a phenomenon that is somehow experienced through the ages.
“A lot of daily forgetfulness is not necessarily because we can’t form new memories, but we can’t find what we want when we need it,” Ranganath said.
“Many of us have the experience of being unable to remember a person’s name or locate where we left our keys, only to have this information appear in our head later,” he added.
This is because people form many similar memories, such as all the people they have met recently or all the places where they may have put the keys. This makes it difficult to select the right information, Ranganath explains.
Amer and colleagues argue that this happens more often as people get older, not because they lose brain plasticity or progress to amnesia, but because of these “disordered memory landscapes.” Memories include destination information (what you are asked to remember) and irrelevant information.
Reduced cognitive control may make it more difficult for older adults to focus on a piece of information because irrelevant information can be “stored in the same memory representation as that contained in the target information,” Amer said. These distractions are related to what the person is trying to remember, and can ultimately affect memory if asked to remember something specific.
Amer illustrates this: One person knows several people named Mike, but they are trying to remember the last name of only one of Mike. As they think about all the Mikes they know, they have to filter out everything they know about these people and delete all the information related to the wrong Mikes. This internal navigation becomes especially difficult when one is older because it becomes more difficult to delete irrelevant information.
This “interpretation [of the data] it’s reasonable, “said André Fenton, a professor of neural science at New York University who is not affiliated with the new paper.” Fenton studies how brains store experiences as memories.
“We often think distractions come from outside, but there are distractions of internal origin,” Fenton said. “I would say internal distraction is much bigger and always harder than external distraction.”
More research is needed to understand why reduced cognitive control can lead to disorder. One proposed explanation relates to the hippocampus, the complex brain structure that plays an important role in learning and memory. It is possible that the hippocampus is “indiscriminately forming these additional associations between all these pieces of information,” Amer said.
In general, there is also a need in the science of memory and aging to include more diverse populations in the study samples, Ranganath said. For example, most research on older adults has been “based on samples of upper-middle-class people, mostly white, highly educated.” He believes that these findings would still be maintained in a larger and more diverse study sample, but this research should definitely be known.
Meanwhile, the memory mess isn’t all that bad. Although “messy” is the preferred phrase in the document, its authors write that the word could be replaced by “enriched” or “elaborate.” While irrelevant information clutter can make it harder to remember a specific detail, excessive knowledge can also help a person in certain situations, such as when it comes to being creative, making a decision, or learning something new. These moments benefit from a comprehensive knowledge.
In turn, it is possible that the paradox of why older adults perform worse on most memory tests despite having more knowledge is explained by something else: the tests themselves.
“There’s this predominant idea in the literature that as we age, we tend to perform worse on memory tests, which is true, but it’s also the result of the types of tests we usually use in the lab,” Amer said. . “These usually require a narrow focus on one piece of information: you have to focus on the information, remember it, and remember it later. These are the kinds of tests that older adults don’t they work well “.
But they perform better than younger adults on different types of tests, those that focus more on creativity and decision making. This suggests that the relationship between aging and performance should be viewed in more nuance, he said. Cognitive ability does not necessarily decrease with age; it depends on the context.
“I think it only helps to know that as we get older, we still have the ability to learn, but we’re not using it the right way,” Ranganath said. “When we see that we’re really getting a lot of information, it helps to alleviate that feeling of helplessness and anxiety that we can feel when we don’t remember something. I’m getting older? “