Previous laboratory research may not have accurately captured older adults’ memory
One of the major cognitive changes that occurs as we age is difficulty recounting the details of past experiences. But two recent studies suggest that older people’s memories may be richer than previously thought.
The idea that describing past experiences becomes more difficult with age is based on decades of laboratory research, says Matthew Grilli, a psychologist at the University of Arizona in Tucson. Laboratory studies of autobiographical memories, which typically involved experimenters asking people about past events, have shown that older adults may remember fewer details than younger adults. The researchers found that this effect was more pronounced in people with dementiawhich leads many to consider this change as a sign of cognitive decline.
Grilli and his colleagues wanted to test whether the data was kept outside the laboratory. In a study whose publication in the Journal of Experimental Psychology: Generalresearchers asked 24 young adults aged 18 to 28 and 50 adults aged 61 to 81 to download a smartphone app that randomly recorded 30 seconds of audio five times per hour for 14 hours per day. After 10 days of continuous recording, researchers sifted through these sound files for moments when people shared autobiographical memories and analyzed the content of those memories. Participants also came to the lab for more traditional assessments, based on in-person interviews.
The team found that in everyday conversations, older adults showed no significant difference in their ability to recount details compared to older adults. their younger counterparts. These findings suggest that researchers “may need to take a step back from the assumptions we make about how autobiographical memories may or may not change with age, based on laboratory research, which may not capture the whole picture,” says Grilli.
These results are supported by another study, published in January in PNASin which Grilli and colleagues assessed the autobiographical memory of more than 1,900 adults aged 18 to 89 using a different smartphone-based technique, which surveyed participants throughout the day to ask them what they were thinking. There, the team found that older people reported their past thoughts with more specificity and vividness than their younger counterparts.
Researchers aren’t sure why these differences between the lab and everyday life only seem to appear in older people. Jessica Andrews-Hanna, a cognitive neuroscientist at the University of Arizona and co-author of both studies, says one reason might be that the lab setting is less familiar to older participants than to younger ones, who are often students on the campus where this type of work is done. Additionally, the experiencers are often young adults themselves, meaning that older adults may feel the need to provide more context before describing the content of their memories.
It’s still unclear whether the participants’ memories were accurate, Andrews-Hanna says. However, she adds, it may be that how people experience and share their memories in daily life are more sensitive markers of disease-related cognitive decline than the accuracy of the descriptions themselves.
“We need more studies of aging that move out of the laboratory and examine memory and related functions in a more naturalistic context,” says Daniel Schacter, a psychologist at Harvard University who was not involved in the work. Factors such as a person’s narrative style may also explain differences in autobiographical memories reported in the lab, he says.
Brian Levine, a scientist at the Baycrest Academy for Research and Education in Toronto who was not involved in this work, points out that aging does affect memory—difficulty remembering details of past episodes is one of the most common complaints of aging—but the way older people use their memories may differ from that of younger adults. “When we take them into the lab and test them on things that are not optimized for their needs, they will look more weakened than they actually are,” he says.
