Summary: Cluttered memory traces and difficulty suppressing irrelevant information make older adults less confident in their recollections, which may increase their vulnerability to persuasion and fraud, a new study reports.
Source: Georgia Institute of Technology
New research from the Georgia Institute of Technology shows that older adults often struggle to recall specific details because their brains more readily retain irrelevant information absorbed unconsciously. This mental “clutter” reduces confidence in memory, even when the memory is accurate, and may help explain why older adults are more susceptible to manipulation.
Researchers monitored brain activity with EEG while older adults (60+) and younger college students viewed pictures of everyday objects. Each object was presented alongside two contextual features — a color and a scene (for example, a living room). Participants were instructed to attend to one contextual feature and ignore the other. After a one-hour delay, participants judged whether each object was new or old and whether the object matched the attended color and scene.
Both age groups could recall the objects themselves and the context they had been asked to attend to reasonably well, but neither group performed well at remembering the context they were told to ignore. The key difference was confidence: older adults were noticeably less sure of their answers.
“When we asked how certain they were, older adults tended to pull back from firm answers,” said Audrey Duarte, associate professor of psychology and lead author of the study. EEG recordings revealed why: older participants’ brains spent more time and effort reconstructing past events when trying to retrieve contextual details.
The researchers describe this extra effort as a brief “mental time travel.” As older adults attempted to piece together the original event, information that should have been filtered out during encoding resurfaced alongside the relevant details. This extra, irrelevant information — the mental clutter — undermined their confidence, even when their recollections were actually correct.
Duarte offers a real-world analogy: imagine two older adults having a conversation at a busy cocktail party. Although they focus on the exchange between them, their brains still absorb background noise — snippets of other conversations, the music, or nearby laughter. Later, when they try to recall the discussion, their memory reconstruction must disentangle the target conversation from the surrounding noise, making recollection less clear and less certain.
By contrast, younger participants retrieved relevant details faster and with less neural effort. EEG measures suggest younger adults were better at preventing irrelevant information from being stored in the first place, preserving a cleaner memory trace and higher confidence at retrieval.
Duarte warns that this reduced confidence has practical consequences. “If you’re unsure about what actually happened, you’re more likely to accept another person’s version of events,” she said. That vulnerability can be exploited in situations such as financial fraud, where perpetrators often try to convince older adults that prior conversations or agreements occurred when they did not.
Funding: This research was supported by the National Science Foundation under Grant No. 1125683. The opinions, findings, conclusions, and recommendations expressed are those of the authors and do not necessarily reflect the views of the National Science Foundation.
Source: Jason Maderer – Georgia Institute of Technology
Image Source: This NeuroscienceNews.com image is in the public domain.
Original Research: Abstract for “Age-related deficits in selective attention during encoding increase demands on episodic reconstruction during context retrieval: An ERP study” by Taylor James, Jonathan Strunk, Jason Arndt, and Audrey Duarte in Neuropsychologia. Published online June 2016. doi:10.1016/j.neuropsychologia.2016.04.009
Georgia Institute of Technology. “Why Seniors Tend to be Less Confident With Their Memories.” NeuroscienceNews. NeuroscienceNews, 14 June 2016.
Abstract
Age-related deficits in selective attention during encoding increase demands on episodic reconstruction during context retrieval: An ERP study
Prior event-related potential (ERP) and neuroimaging studies indicate that focusing attention on item-context associations at encoding improves later context memory and reduces the need for strategic retrieval in both younger and older adults. Everyday experiences, however, present multiple competing features that vie for attention. This study examined how directing attention to one contextual feature while attempting to ignore another affects context memory and the neural processes supporting retrieval in young and older adults. Participants studied objects presented with two contextual features (a color and a scene), attending to the object’s relationship with just one feature. Later, they made context memory judgments for both the attended and unattended features and rated their confidence.
Behavioral results showed that while both age groups could apply selective attention at encoding, older adults were less confident in their context memory for attended features and displayed greater dependence between memory for attended and unattended features — a pattern described as hyper-binding. ERP results were broadly similar across ages, but older adults exhibited a more pronounced late posterior negativity (LPN), a neural signature associated with episodic reconstruction. The authors conclude that age-related difficulties suppressing irrelevant information at encoding reduce the selectivity of context memory, thereby increasing demands on reconstruction processes when specific details are not readily available during retrieval.
“Age-related deficits in selective attention during encoding increase demands on episodic reconstruction during context retrieval: An ERP study” by Taylor James, Jonathan Strunk, Jason Arndt, and Audrey Duarte in Neuropsychologia. Published online June 2016. doi:10.1016/j.neuropsychologia.2016.04.009