Nebes R D, Brady C B, Huff F J
Department of Psychiatry, University of Pittsburgh, PA.
J Clin Exp Neuropsychol. 1989 Mar;11(2):219-30. doi: 10.1080/01688638908400884.
Previous studies using a word-naming task have suggested that in demented patients, semantic priming results only from automatic spreading activation and not from attention-dependent processes. If this is true, then on a lexical-decision task where attention-dependent processes are a major source of the semantic-priming effect, demented patients should show little or no priming. To test this prediction, three groups of 16 subjects (young and normal-old individuals and patients with Alzheimer's disease) were given a Word-Naming and a Lexical-Decision task. In both tasks, the amount of semantic priming (the difference in response time to a word preceded by a semantically unassociated vs. a semantically associated word) was determined. Demented patients showed significantly greater semantic priming than either normal group on both tasks. This result argues against the hypothesis that the semantic priming found in demented patients is due solely to automatic processes.
以往使用单词命名任务的研究表明，在痴呆患者中，语义启动仅源于自动扩散激活，而非依赖于注意力的过程。如果这是真的，那么在词汇判断任务中，由于依赖于注意力的过程是语义启动效应的主要来源，痴呆患者应该几乎没有或根本没有启动效应。为了验证这一预测，对三组各16名受试者（年轻和正常老龄个体以及阿尔茨海默病患者）进行了单词命名和词汇判断任务。在这两项任务中，都测定了语义启动的量（对语义不相关词与语义相关词之前的单词的反应时间差异）。痴呆患者在两项任务中均表现出比正常组显著更大的语义启动效应。这一结果与痴呆患者中发现的语义启动仅归因于自动过程的假设相悖。
