Abeysinghe S C, Bayles K A, Trosset M W
Department of Speech and Hearing Sciences, University of Arizona.
J Speech Hear Res. 1990 Sep;33(3):574-82.
The nature of semantic memory impairment in 23 persons with dementia of the Alzheimer type (DAT) was studied using three semantic tasks: word association, definition, and associate rank ordering. Using hierarchical log-linear analysis of the responses to the word association task, DAT subjects were more likely than normal control subjects to give multiword, repetitious, or unrelated responses. Additionally, the ratio of paradigmatic to syntagmatic responses was significantly decreased in DAT subjects. Surprisingly, DAT subjects were able to provide definitions for many stimulus words for which they were unable to provide meaningful associates. This finding suggests the need for caution in interpreting a decrease in the number of paradigmatic responses as indicative of a loss of conceptual knowledge. Results of other analyses demonstrated that DAT subjects had significant impairment in identifying highly related and unrelated semantic associates of words. Taken together, results of this study indicate that one feature of DAT is deterioration in the associative relations between concepts.
利用三项语义任务（词语联想、定义及联想等级排序），对23名阿尔茨海默型痴呆（DAT）患者语义记忆损害的性质进行了研究。通过对词语联想任务的反应进行分层对数线性分析，发现DAT患者比正常对照受试者更有可能给出多词、重复或无关的反应。此外，DAT患者中范例性反应与组合性反应的比例显著降低。令人惊讶的是，DAT患者能够为许多刺激词提供定义，但却无法提供有意义的联想词。这一发现表明，在将范例性反应数量的减少解释为概念性知识丧失的指标时需要谨慎。其他分析结果表明，DAT患者在识别词语的高度相关和不相关语义联想方面存在显著损害。综合来看，本研究结果表明，DAT的一个特征是概念之间的联想关系恶化。
