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bioRxiv · 10.1101/2024.04.25.591227

Effects of Age on Cross-Cultural Differences in the Neural Correlates of Memory Retrieval

Abstract

Culture can shape memory, but little research investigates age effects. The present study examines the neural correlates of memory retrieval for old, new, and similar lures in younger and older Americans and Taiwanese. Results show that age and culture impact discrimination of old from new items. Taiwanese performed worse than Americans, with age effects more pronounced for Taiwanese. Americans activated the hippocampus for new more than old items, but pattern of activity for the conditions did not differ for Taiwanese, nor did it interact with age. The engagement of left inferior frontal gyrus (LIFG) differed across cultures. Patterns of greater activity for old (for Americans) or new (for Taiwanese) items were eliminated with age, particularly for older Americans. The results are interpreted as reflecting cultural differences in orientation to novelty vs. familiarity for younger, but not older, adults, with the LIFG supporting interference resolution at retrieval. Support is not as strong for cultural differences in pattern separation processes. Although Americans had higher levels of memory discrimination than Taiwanese and engaged the LIFG for correct rejections more than false alarms, the patterns of behavior and neural activity did not interact with culture and age. Neither culture nor age impacted hippocampal activity, which is surprising given the regions role in pattern separation. The findings suggest ways in which cultural life experiences and concomitant information processing strategies can contribute to consistent effects of age across cultures or contribute to different trajectories with age in terms of memory.

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BibTeXRIS

Cho, I., Leger, K. R., Valoumas, I., Mair, R. W., Goh, J. O. S., Gutchess, A.. 2024-04-28. Effects of Age on Cross-Cultural Differences in the Neural Correlates of Memory Retrieval. https://doi.org/10.1101/2024.04.25.591227

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