Supplementary Material for: Language in healthy ageing: A comparison across language domains

Introduction: Life expectancy has been increasing in recent decades. Therefore, it is important to understand the functional changes during healthy ageing. Most research has mainly focused on one linguistic domain at a time. The current study aimed at investigating whether changes in language performance in healthy ageing occur in some language domains more than in others. Methods: Twenty-three older healthy Hebrew-speaking adults, exhibiting no cognitive decline, were examined on tasks aimed at testing their performance in different language and cognitive domains: lexical retrieval, complementation information, syntax, Theory of Mind (a domain related to pragmatic aspects of language) and short-term memory. We compared their performance at both the group and the individual levels. Comparisons were made between the performance of the older adults and control data of young adults, and between the older adults' performance in the different linguistic domains. In addition, correlations between the older adults' phonological short-term memory abilities and their performance in various linguistic domains were examined. Results: A decline was found in several linguistic domains among the older adults, while in other domains no decline was found. However, no unequivocal decline in linguistic functioning was found due to relatively large variance in their performance. Conclusion: Not all linguistic domains are equally vulnerable in ageing, and not all older adults are equally affected. The research has both clinical and theoretical implications.

引言：近数十年来，人类预期寿命持续攀升。因此，探究健康老龄化进程中的功能变化具有重要的学术与现实意义。既往多数研究多聚焦于单一语言领域。本研究旨在探究健康老龄化人群的语言能力变化是否在部分语言领域中表现得更为显著。
方法：招募23名无认知衰退的健康希伯来语老年成年人，通过多项任务测试其在不同语言与认知领域的表现：词汇提取、补全信息、句法、心理理论（Theory of Mind，与语言语用维度相关的领域）以及短时记忆。本研究从群体与个体两个层面开展比较分析：一方面将老年人群的表现与青年成年人的对照数据进行对比，另一方面比较老年人在不同语言领域的表现差异；此外，还分析了老年人群的语音短时记忆能力与其在各语言领域的表现之间的相关性。
结果：研究发现，老年人群在部分语言领域出现能力下降，而在其他领域则未表现出显著衰退。但由于个体表现存在较大变异，未观察到语言功能存在明确一致的衰退现象。
结论：并非所有语言领域在老龄化过程中均易受损，且不同老年人受衰老的影响程度亦存在显著差异。本研究兼具临床应用与理论研究双重价值。