Computational research suggests that semantic memory, operationalized as semantic memory networks, undergoes age-related changes. Previous work suggests that concepts in older adults’ semantic memory networks are more separated, more segregated, and less connected to each other. However, cognitive network research often relies on group averages (e.g., young vs. older adults), and it remains unclear if individual differences influence age-related disparities in language production abilities. Here, we analyze the properties of younger and older participants’ individual-based semantic memory networks based on their semantic relatedness judgments. We related individual-based network measures—clustering coefficient (CC; connectivity), global efficiency, and modularity (structure)—to language production (verbal fluency) and vocabulary knowledge. Similar to previous findings, we found significant age effects: CC and global efficiency were lower, and modularity was higher, for older adults. Furthermore, vocabulary knowledge was significantly related to the semantic memory network measures: corresponding with the age effects, CC and global efficiency had a negative relationship, while modularity had a positive relationship with vocabulary knowledge. More generally, vocabulary knowledge significantly increased with age, which may reflect the critical role that the accumulation of knowledge within semantic memory has on its structure. These results highlight the impact of diverse life experiences on older adults’ semantic memory and demonstrate the importance of accounting for individual differences in the aging mental lexicon.
|Number of pages||16|
|Journal||Psychology and Aging|
|Early online date||23 Jan 2023|
|State||Published - 23 Jan 2023|
Bibliographical noteFunding Information:
This publication was supported by funding from the National Institutes of Health, National Institute on Aging NIH NIA Grant R01 AG034138 awarded to Michele T.Diaz. The content is solely the responsibility of the authors and does not necessarily represent the official views of the funding agencies. The authors thank Brendan Baker for helping in programming the online experiment. Preliminary results and analyses of this project were reported at the 2022 International Workshop on Language Production.
© 2023 American Psychological Association
- individual differences
- semantic memory
- semantic networks