The effects of cognitive changes across the adult lifespan on lexical and grammatical processing

预期寿命在上个世纪急剧上升，增加了许多与年龄相关的挑战，其中包括认知的变化。然而，虽然衰老对认知的某些方面（如处理速度、陈述性记忆）的影响已经得到了很好的研究，但对语言关键能力的年龄相关变化以及非语言认知的年龄相关变化与语言处理的变化之间是否存在关系知之甚少。本项目旨在研究年龄在20岁至90岁之间的参与者语言处理的发展轨迹。使用横向参与者设计，我将检查词形简单和复杂单词的产生和理解，并将这些发现与认知任务（处理速度，记忆）的结果联系起来。形态学处理被认为包括语法处理（规则/默认形式）和词汇处理（不规则/非默认形式）。出于这个原因，词形复杂的单词是一个特别好的测试案例，因为它们允许研究语言处理不同机制的老化效应。工作包（WP） 1使用引出生产和跨模态启动来检查复数名词的理解和生产。特别令人感兴趣的是默认和非默认复数之间的（预期的）对比，以及年龄对这些不同复数类型的处理是否有不同的影响。WP 2通过图片命名和词汇决策任务来评估年龄如何影响说话者对形态简单词汇的产生和理解。通过这种方式，我们可以评估衰老是否以类似的方式影响复杂和简单单词的处理，特别是关于变化的开始和整个生命的轨迹。工作包3研究了在WPs 1和WPs 2中发现的衰老对语言处理的影响如何与非语言认知的年龄相关变化联系起来，重点关注一般处理速度和两种主要的学习和记忆系统，陈述性和程序性记忆。具体来说，这项工作的结果将解决衰老是否对语言处理（即词汇和语法过程）产生全面影响的问题，或者这种影响是否更具选择性，某些方面的处理受到的影响比其他方面更大。除了揭示衰老如何影响语言这一主要目标之外，这项研究还应该有助于提供关于衰老（独立于语言）和语言（独立于衰老）的见解。该研究还可能具有翻译影响，因为研究结果可能为影响语言的年龄相关疾病（例如阿尔茨海默病）的研究提供基线。

Life expectancy has risen dramatically in the last century, increasing many age-related challenges, which include changes to cognition. However, while the effects of aging on some aspects of cognition (e.g., processing speed, declarative memory) are quite well-studied, much less is known about age-related changes in the critical capacity of language and whether there is a relation between age-related changes in non-linguistic cognition and changes in language processing.The proposed project investigates the developmental trajectory of language processing in participants between the ages of 20 and 90 years. Using a cross-sectional within-participants design, I will examine the production and comprehension of morphologically simple and complex words and relate those findings to results from cognitive tasks (processing speed, memory). Morphological processing has been argued to involve both grammatical processing (regular/default forms) and lexical processing (irregular/non-default forms). For this reason, morphologically complex words make for a particularly good test case as they allow for the study of aging effects on different mechanisms of language processing.Work package (WP) 1 examines the comprehension and production of plural nouns using elicited production and cross-modal priming. Of particular interest is the (expected) contrast between default and non-default plurals, and whether aging affects the processing of these different plural types differently. WP 2 assesses how aging affects speakers’ production and comprehension of morphologically simple words using picture naming and lexical-decision tasks. This way, we can assess whether aging affects the processing of complex and of simple words in a similar manner, particularly regarding the onset of changes and the trajectory throughout life.Work Package 3 investigates how the effects of aging on language processing found in WPs 1 and 2 can be tied to age-related changes in non-linguistic cognition, with a focus on general processing speed and the two main learning-and-memory systems, declarative and procedural memory. Specifically, the results from this WP will address the question of whether aging exhibits global effects on language processing (i.e., on lexical and grammatical processes alike), or whether the effects are more selective, with some aspects of processing being more greatly affected than others.Besides the main goal – revealing how aging affects language –, this study should also help provide insights about aging (independent of language) and insights about language (independent of aging). The research may also have translational impacts as the findings may provide as baseline for the study of age-related disorders affecting language (e.g., Alzheimer’s disease).