Specht Karsten, Holtel Chrisitane, Zahn Roland, Herzog Hans, Krause Bernd J, Mottaghy Felix M, Radermacher Irmgard, Schmidt Daniela, Tellmann Lutz, Weis Susanne, Willmes Klaus, Huber Walter
Division of Neurolinguistics, Neurology Department, University Hospital Aachen, Aachen, Germany.
Neurosci Lett. 2003 Jul 24;345(3):177-81. doi: 10.1016/s0304-3940(03)00494-4.
In this functional positron emission tomography study brain activations during an auditory lexical decision task with two experimental conditions were investigated. First, the subjects had to discriminate between real words and nonwords; second, real words varied with pseudowords. Comparing each of these tasks to an auditory control condition we found bilateral activation of the superior temporal and inferior frontal gyrus, lateralized to the left in the pseudoword condition. The comparison of the lexical decision tasks revealed higher rCBF during the pseudo-/real word decisions within BA 47, adjacent to Broca's area, and the anterior cingulate. The data support the notion that the lexical decision during a nonword task is mainly based on a phonological discrimination process, whereas a pseudoword task more strongly requires lexical access resulting in activation of BA 47.
在这项功能性正电子发射断层扫描研究中，我们调查了在两种实验条件下的听觉词汇判断任务期间的大脑激活情况。首先，受试者必须区分真实单词和非单词；其次，真实单词与假词进行对比。将这些任务中的每一个与听觉对照条件进行比较，我们发现双侧颞上回和额下回激活，在假词条件下偏向左侧。词汇判断任务的比较显示，在与布洛卡区相邻的BA 47以及前扣带中，假词/真实单词判断期间的局部脑血流较高。数据支持这样的观点，即非单词任务中的词汇判断主要基于语音辨别过程，而假词任务更强烈地需要词汇通达，从而导致BA 47激活。
