Elvevåg B, Weinstock D M, Akil M, Kleinman J E, Goldberg T E
Clinical Brain Disorders Branch, National Institutes of Mental Health, National Institutes of Health, Room 4S235, MSC 1379, Building 10, Bethesda, MD 20892, USA.
Schizophr Res. 2001 Sep 1;51(2-3):119-26. doi: 10.1016/s0920-9964(00)00053-0.
Previous studies have reported significant impairment on verbal fluency tasks (semantic and letter) among schizophrenic subjects. However, the possibility of specific categorical deficits has not been adequately investigated. Nor have the effects of task duration, the stability between testing sessions, and the relationship between intelligence and performance on fluency been thoroughly studied. We performed a series of 3 min fluency tasks (semantic/syntactic and letter) to determine whether duration specific or category-specific differences exist between schizophrenic subjects and normal controls. Each subject was tested at three different times as a means of estimating word pool and assessing the stability of fluency output. Subjects were asked to generate exemplars from each of four semantic/syntactic categories (animals, tools, common nouns and verbs) and three letters (G, E and T). Data from 13 schizophrenic subjects and 15 sex-, age- and pre-morbid-IQ-matched control subjects revealed that patients' overall performance on both the semantic and letter fluency tasks was impaired. While differential impairment on specific semantic categories was noted between groups, no differential effects relating to task duration or testing session were present. Further, by comparing the number of novel words produced in the three testing sessions, we found the groups to be equivalent, a finding we take to suggest that schizophrenic patients' lexicon is intact. Covarying current IQ eliminated the group difference robustly for letter fluency, while only marginally for semantic fluency. Our data revealed the presence of impairment in semantic and letter fluency tasks in schizophrenic patients consistent with previous reports, and also that patients were differentially impaired on semantic categories.
先前的研究报告称，精神分裂症患者在语言流畅性任务（语义和字母）方面存在显著损害。然而，特定类别缺陷的可能性尚未得到充分研究。任务持续时间、测试环节之间的稳定性以及智力与流畅性表现之间的关系也未得到深入研究。我们进行了一系列3分钟的流畅性任务（语义/句法和字母），以确定精神分裂症患者与正常对照组之间是否存在持续时间特异性或类别特异性差异。每个受试者在三个不同时间接受测试，以此来估计词汇储备并评估流畅性输出的稳定性。受试者被要求从四个语义/句法类别（动物、工具、普通名词和动词）以及三个字母（G、E和T）中分别生成示例。来自13名精神分裂症患者和15名性别、年龄及病前智商匹配的对照受试者的数据显示，患者在语义和字母流畅性任务上的总体表现均受损。虽然两组之间在特定语义类别上存在差异损害，但在任务持续时间或测试环节方面没有差异效应。此外，通过比较三次测试环节中产生的新单词数量，我们发现两组相当，这一发现表明精神分裂症患者的词汇表是完整的。对当前智商进行协变量分析后，字母流畅性方面的组间差异得到了有力消除，而语义流畅性方面仅略有消除。我们的数据表明，精神分裂症患者在语义和字母流畅性任务中存在损害，这与先前的报告一致，并且患者在语义类别上存在差异损害。
