Older people struggle to remember important details because their brains can’t resist the irrelevant “stuff” they soak up subconsciously.
Researchers looked at brain activity from EEG sensors and saw that older participants wandered into a brief “mental time travel” when trying to recall details. This journey into their subconscious veered them into a cluttered space that was filled with both relevant and irrelevant information.
The clutter can lead to less confidence—even when recollections are correct—and is one reason older people are more susceptible to manipulation, researchers say.
For the study, published in the journal Neuropsychologia, researchers showed older adults (60 years and older) and college students a series of pictures of everyday objects while EEG sensors were connected to their heads. Each photo was accompanied by a color and scene (e.g., living room). Participants were told to focus on one and ignore the other. An hour later, they were asked if the object was new or old, and if it matched the color and the scene.
Neither age group was very good at recalling what they were told to ignore. Both did well remembering the object and what they were supposed to focus on.
“But when we asked if they were sure, older people backed off their answers a bit. They weren’t as sure,” says Audrey Duarte, associate professor of psychology at Georgia Institute of Technology.
Researchers noticed differences in brain activity between the young and old. Older adults’ brains spent more time and effort trying to reconstruct their memories.
“While trying to remember, their brains would spend more time going back in time in an attempt to piece together what was previously seen,” Duarte says. “But not just what they were focused on—some of what they were told to ignore got stuck in their minds.”
Duarte uses a cocktail party as an example: Two older people are talking to each other. And even though they’re only concentrating on the conversation, their brains absorb the other noise in the room.
“When it’s time to remember the conversation, they may struggle a bit to recall some details. That’s because their brains are also trying to decipher the other noises,” she says. “What music was playing? What was the couple next to them saying? That extra stuff shouldn’t be in their memories at all, but it is. And it negatively impacts their ability to clearly remember the conversation.”
Younger people were quicker to recall details and used less brain power. The irrelevant information was never stored in the first place, which kept their memories relatively clutter-free. And that’s why they were more confident than the older participants when remembering relevant details.
A lack of confidence, Duarte says, can lead to manipulation.
“If someone tells you that you should remember it one way, you can be more easily persuaded if you lack confidence. This memory clutter that’s causing low confidence could be a reason why older adults are often victims of financial scams, which typically occur when someone tries to trick them about prior conversations that didn’t take place at all.”
The National Science Foundation supported the work.
Source: Georgia Institute of Technology
