In a neuropsychological assessment, each test aims at measuring a single cognitive function. However, test performance depends on an interconnected system of cognitive functions and individual characteristics. For a better understanding of cognitive deficits, it is fundamental to recognize this complexity and study the relationships between test performances. This study aims to evaluate complexity in neuropsychological assessment through network analysis (NA) in 165 healthy older adults, 191 patients with Alzheimer's disease (AD), and 129 patients with vascular encephalopathy (VaE). NA is a flexible method to explore different domains where many variables are correlated with each other, and the relationships are key for understanding the domains. We included general aspects of individual differences (i.e., age, sex, years of education) and the raw scores of a clinically used neuropsychological battery in the network. Healthy subjects showed a segregated pattern, suggesting a good specificity of each test in measuring a specific cognitive function. Moreover, the scores were related to age and education. In the patient groups, the identified patterns changed in a consistent manner, showing less specificity and new relationships between the various tests, thereby reducing the impact of age and education on the performance. In particular, AD patients showed worse performance on the tests but also a different balance between different tasks, suggesting a reorganization of the cognitive system and not a mere decline. These results provide a new perspective in looking at the complexity of cognitive function assessment.

中文翻译：

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认知障碍神经心理学评估的复杂性：一种网络分析方法。

在神经心理学评估中，每个测试旨在测量单个认知功能。但是，测试性能取决于认知功能和个人特征的相互联系的系统。为了更好地理解认知缺陷，识别这种复杂性并研究测试表现之间的关系至关重要。这项研究旨在通过网络分析（NA）对165名健康的老年人，191名阿尔茨海默氏病（AD）和129名血管性脑病（VaE）患者进行神经心理学评估，以评估其复杂性。NA是一种灵活的方法，可用于探索多个变量相互关联的不同领域，而关系是理解这些领域的关键。我们纳入了个体差异的一般方面（例如，年龄，性别，年的教育）和网络中临床使用的神经心理学电池的原始分数。健康的受试者表现出分离的模式，表明每种测试在测量特定的认知功能方面具有良好的特异性。而且，分数与年龄和教育程度有关。在患者组中，识别出的模式以一致的方式改变，显示出不同的特异性和各种测试之间的新关系，从而减少了年龄和教育程度对表现的影响。尤其是，AD患者在测试中表现较差，但在不同任务之间也表现出不同的平衡，这表明认知系统得以重组，而不仅仅是下降。这些结果为研究认知功能评估的复杂性提供了新的视角。