Just like trying to tell the difference between a picture of a dream and a picture of sleep, older adults face greater difficulty in distinguishing between words they’ve actually heard and words that are similar but not quite right. This study explored how age affects the brain’s ability to discriminate and remember auditory words. The results showed that older adults had lower accuracy in recognizing true words and were more likely to confidently mistake false words for real ones. The researchers used fancy brain scans to look at the neural activity during memory retrieval and found that older adults had weaker patterns of activation in specific brain regions compared to younger adults. Specifically, the primary auditory cortex, which processes sound, was less able to differentiate between studied words and unstudied words in older adults. Additionally, the prefrontal cortex, involved in monitoring and decision-making, showed reduced activity when older adults encountered similar but incorrect words. These findings suggest that age-related changes in neural discriminability and prefrontal monitoring contribute to difficulties in memory retrieval for auditory information. To dive deeper into this fascinating research, check out the full article linked below!

After hearing a list of words (e.g., dream, awake, and bed), older adults tended to have more difficulty than younger adults in distinguishing targets (e.g., dream) from lures (e.g., sleep) and foils (e.g., pen) in a visual recognition test. Age-related reduction in neural discriminability in the visual cortex has been linked to deficits in memory discriminability of pictures. However, no study has examined age differences in auditory discrimination and prefrontal monitoring during true and false memory retrieval after hearing words. The current study used a visual recognition test following an auditory study of words and showed that older adults had lower true recognition and higher propensity for high-confidence false recognition compared to young adults. Using classification-based multivariate pattern analysis for functional neuroimaging data during memory retrieval, we found that neural activation patterns in the primary auditory cortex could be used to distinguish between auditorily-studied targets and unstudied lures in young adults, but not in older adults. Moreover, prefrontal monitoring for lures was weaker in older adults as compared to young adults. Individual differences analysis showed that neural discriminability in the primary auditory cortex was positively related to true recognition, whereas prefrontal activation for lures was negatively related to the propensity for high-confidence false recognition in young adults but not in older adults. Together, age differences in true and false memories following auditory study are associated with reduced neural discriminability in the primary auditory cortex and reduced prefrontal monitoring during retrieval.

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