Mueller Kimberly D, Hermann Bruce, Mecollari Jonilda, Turkstra Lyn S
a Department of Communication Sciences and Disorders , University of Wisconsin-Madison , Madison , WI , USA.
b Wisconsin Alzheimer's Institute , University of Wisconsin-Madison , Madison , WI , USA.
J Clin Exp Neuropsychol. 2018 Nov;40(9):917-939. doi: 10.1080/13803395.2018.1446513. Epub 2018 Apr 19.
The neuropsychological profile of people with mild cognitive impairment (MCI) and Alzheimer's disease (AD) dementia includes a history of decline in memory and other cognitive domains, including language. While language impairments have been well described in AD dementia, language features of MCI are less well understood. Connected speech and language analysis is the study of an individual's spoken discourse, usually elicited by a target stimulus, the results of which can facilitate understanding of how language deficits typical of MCI and AD dementia manifest in everyday communication. Among discourse genres, picture description is a constrained task that relies less on episodic memory and more on semantic knowledge and retrieval, within the cognitive demands of a communication context. Understanding the breadth of evidence across the continuum of cognitive decline will help to elucidate the areas of strength and need in terms of using this method as an evaluative tool for both cognitive changes and everyday functional communication.
We performed an extensive literature search of peer-reviewed journal articles that focused on the use of picture description tasks for evaluating language in persons with MCI or AD dementia. We selected articles based on inclusion and exclusion criteria and described the measures assessed, the psychometric properties that were reported, the findings, and the limitations of the included studies.
36 studies were selected and reviewed. Across all 36 studies, there were 1, 127 patients with AD dementia and 274 with MCI or early cognitive decline. Multiple measures were examined, including those describing semantic content, syntactic complexity, speech fluency, vocal parameters, and pragmatic language. Discriminant validity widely reported and distinct differences in language were observable between adults with dementia and controls; fewer studies were able to distinguish language differences between typically aging adults and those with MCI.
Our review shows that picture description tasks are useful tools for detecting differences in a wide variety of language and communicative measures. Future research should expand knowledge about subtle changes to language in preclinical AD and Mild Cognitive Impairment (MCI) which may improve the utility of this method as a clinically meaningful screening tool.
轻度认知障碍（MCI）和阿尔茨海默病（AD）痴呆患者的神经心理学特征包括记忆及其他认知领域（包括语言）衰退的病史。虽然AD痴呆中的语言障碍已得到充分描述，但MCI的语言特征却鲜为人知。连贯言语和语言分析是对个体口语语篇的研究，通常由目标刺激引发，其结果有助于理解MCI和AD痴呆典型的语言缺陷在日常交流中是如何表现的。在语篇体裁中，图片描述是一项受限任务，在交流情境的认知需求范围内，它较少依赖情景记忆，更多依赖语义知识和检索。了解认知衰退连续体上证据的广度，将有助于阐明在将该方法用作认知变化和日常功能交流评估工具方面的优势领域和需求领域。
我们对同行评审期刊文章进行了广泛的文献检索，这些文章聚焦于使用图片描述任务评估MCI或AD痴呆患者的语言。我们根据纳入和排除标准选择文章，并描述所评估的测量方法、报告的心理测量特性、研究结果以及纳入研究的局限性。
共筛选并综述了36项研究。在所有36项研究中，有1127例AD痴呆患者以及274例MCI或早期认知衰退患者。研究考察了多种测量方法，包括描述语义内容、句法复杂性、言语流畅性、语音参数和语用语言的方法。广泛报道了判别效度，且痴呆成年人与对照组之间在语言方面存在明显差异；能够区分典型老年成年人和MCI患者语言差异的研究较少。
我们的综述表明，图片描述任务是检测多种语言和交流测量差异的有用工具。未来的研究应扩展对临床前AD和轻度认知障碍（MCI）中语言细微变化的认识，这可能会提高该方法作为具有临床意义的筛查工具的效用。
