INTRODUCTION Previous research suggests that specific symbol features attenuate symbol comprehension deficits in seniors suffering from Alzheimer disease dementia (ADD). However, it remains unclear whether these findings also apply to other disorders associated with cognitive dysfunctions. METHODS Ninety healthy controls, 30 patients with major depressive disorder (MDD), 35 patients with mild cognitive impairment (MCI), and 55 patients with ADD performed a Symbol Processing Task with 4 different symbol categories. Nonparametric between×within subjects analyses were conducted to examine the impact of different symbol categories on performance accuracy in all experimental groups. RESULTS Analyses revealed a higher symbol comprehension accuracy in healthy seniors than in MDD, MCI, and ADD patients, with the lowest accuracy rates shown by ADD patients. Although the type of symbol hardly affected performance accuracy in healthy seniors and MDD patients, different symbol categories influenced the performance of MCI and ADD patients significantly. CONCLUSIONS Our findings indicate that symbols with distracting features impede symbol comprehension in ADD and MCI. Symbols with visual cues, by contrast, facilitate symbol comprehension in ADD and may even be advantageous over standardized symbols used in public life.

中文翻译：

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阿尔茨海默氏病痴呆，轻度认知障碍和重度抑郁症患者的符号理解。

引言先前的研究表明，特定的符号特征可减轻患有阿尔茨海默氏病痴呆症（ADD）的老年人的符号理解能力缺陷。但是，尚不清楚这些发现是否也适用于与认知功能障碍相关的其他疾病。方法90名健康对照者，30名重度抑郁症（MDD），35名轻度认知障碍（MCI）和55名ADD患者执行了4种不同符号类别的符号处理任务。进行了受试者之间×受试者之间的非参数分析，以检验所有实验组中不同符号类别对性能准确性的影响。结果分析显示，健康老年人的符号理解准确度高于MDD，MCI和ADD患者，具有ADD患者显示的最低准确率。尽管符号的类型几乎不会影响健康的老年人和MDD患者的性能准确性，但是不同的符号类别会显着影响MCI和ADD患者的性能。结论我们的发现表明具有分散注意力特征的符号会阻碍ADD和MCI中的符号理解。相比之下，具有视觉提示的符号有助于ADD中的符号理解，甚至可能优于公共生活中使用的标准化符号。