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bioRxiv · 10.1101/303859

Age-related impairment of semantic integration into long-term memory is related to theta-alpha and low beta oscillations

Packard, P. A.·Steiger, T.·Fuentemilla, L.·Bunzeck, N.
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Abstract

Long-term memory can improve when incoming information is congruent with known semantic information. This so-called congruence effect has widely been shown in younger adults but age-related changes and neural mechanisms remain unclear. Here, congruence improved recognition memory in younger and older adults (i.e. congruency effect), but - importantly - this effect decreased with age. Electroencephalography data show that, in both groups, congruence led to widespread differences in event-related potentials (ERPs) and alpha-beta oscillations (8-30 Hz), known to support semantic processing. Importantly, these ERP differences predicted increases in memory performance, especially for congruent items. Finally, age-related differences in memory were accompanied by a positive ERP and later decrease in theta-alpha (5-13 Hz) during encoding, which were greater in the younger group. Together, although semantic congruence generally increases long-term memory, the effect is less pronounced in the elderly. At the neural level, theta-alpha oscillations, previously linked to memory and attentional processes, provide a mechanistic explanation for such an age-related effect.

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Packard, P. A., Steiger, T., Fuentemilla, L., Bunzeck, N.. 2018-04-18. Age-related impairment of semantic integration into long-term memory is related to theta-alpha and low beta oscillations. https://doi.org/10.1101/303859

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