The age-related effect on electrophysiological correlates of successful episodic memory encoding supports the hypothesis of a deficit in self-initiated encoding processes in aging

• Published in: Neuroscience letters Vol. 781; p. 136676
• Main Authors: Bouazzaoui, Badiâa, Angel, Lucie, Sacher, Mathilde, Fay, Séverine, Alibran, Emilie, Pylouster, Jean, Gautier, Raphaël, Taconnat, Laurence
• Format: Journal Article
• Language: English
• Published: Ireland Elsevier B.V 11.06.2022; Elsevier
• Subjects: Aged; Aging; Aging - physiology; Cognition - physiology; Cognitive science; Electroencephalography - methods; Encoding strategies; Episodic memory; ERPs; Evoked Potentials - physiology; Humans; Memory Disorders; Memory, Episodic; Mental Recall - physiology; Neuroscience; Psychology; Young Adult; ERPs; Aging; Episodic memory; Encoding strategies; encoding strategies; aging
• ISSN: 0304-3940; 1872-7972
• DOI: 10.1016/j.neulet.2022.136676

•Episodic memory declines with advancing age.•Age effect may be due to the absence of an environmental support.•Neural correlates of encoding processes differ between young and older adults.•Younger adults show a sustained brain activity from parietal to frontal areas.•Older adults show shorter brain activity more in the parietal than frontal areas. Episodic memory decline with aging may be due to an age-related deficit in encoding processing, older adults having increasing difficulty to self-initiate encoding strategies that support later retrieval. Using event-related potentials (ERPs), the present study explored for the first time the neural correlates of successful encoding in a resource-dependent episodic memory task, in which participants had to self-initiate processes at both encoding and retrieval. At the behavioral level, results confirm the better memory performance of young than older adults. Comparing the neural activity elicited by studied items that were and were not subsequently recalled (Subsequent Memory Effect, SME), electrophysiological data revealed that younger adults showed a significant and sustained SME, shifting from parietal to frontal areas, suggesting that they self-initiated deep encoding strategies. In older adults, the duration of brain activity was shorter and located more in the parietal than frontal areas, suggesting that they used shallow rather than deep processes. Consistent with the hypothesis of a deficit in self-initiated strategies in aging, our findings suggest that when older adults are faced with a difficult memory task (no encoding support and no cue at retrieval), they engage fewer elaborative strategies than young adults, resulting in impaired episodic memory performance.