How Retrieval Processes Change with Age: Exploring Age Differences in Semantic Network and Retrieval Dynamics

This study aimed to investigate the impact of age on semantic memory networks and retrieval dynamics using a single-list free recall paradigm. A total of 318 participants, including younger (n = 175) and older adults (n = 143), completed the Word Recall test to assess delayed recall performance. Significant differences in network structure were observed, with the older group displaying higher average shortest path length and modularity values, while the younger group had a higher cluster coefficient. In terms of retrieval dynamics, both groups exhibited a temporal contiguity effect with forward asymmetry. However, older adults showed a reduced temporal contiguity effect compared to the younger group. Additionally, this study examined subgroups of participants who implemented idiosyncratic strategies. Two subgroups diverged from the average retrieval dynamic curves, with one relying on non-temporal mechanisms and the other employing a backward direction to support memory search. Participants who employed temporal associations in a forward direction demonstrated the highest recall performance compared to other strategies. Overall, this study suggests that the lower free recall performance in the older group may be attributed to a reduced ability to reinstate temporal context information for guiding retrieval and differences in the semantic memory network structure, with older adults exhibiting a less flexible and small-world-like structure. peerReviewed other