Heim Stefan, Alter Kai
Institute of Medicine, Research Centre Jülich, 52425 Jülich, Germany.
Acta Neurobiol Exp (Wars). 2006;66(1):55-68. doi: 10.55782/ane-2006-1587.
We used event-related potentials (ERPs) and acoustic analyses to investigate the processing of prosodic pitch accents as a function of their position in a sentence. Accents in sentence-medial positions were characterized by a higher fundamental frequency (F0) and an increased duration. They elicited two different negative ERP components around 400 ms, depending on the predictability of the accent. When the accent was predictable, the negativity was fronto-laterally distributed and identified as the previously known Expectancy Negativity. Unpredictable accents elicited a more broadly distributed N400 with a central maximum, reflecting difficulties in semantic processing. For sentence-initial pitch accents, words had a higher F0 but of the same duration as sentence-initial words without pitch accents. These pitch accents elicited a P200 but no negativity in a 400 ms time window. The P200 was modulated by the onset latency of the F0 peak rather than its magnitude. We discuss the possibility of a delayed processing of sentence-initial accents when the actual occurrence of an F0 peak can be identified by comparing the F0 of the sentence-initial word to a reduced F0 of a word occurring later in the sentence.
我们使用事件相关电位（ERP）和声学分析来研究韵律音高重音的处理过程，该过程是句子中重音位置的函数。句中位置的重音特征在于更高的基频（F0）和更长的持续时间。根据重音的可预测性，它们在400毫秒左右引发了两种不同的负性ERP成分。当重音可预测时，负性成分在前额-外侧分布，并被确定为先前已知的预期负波。不可预测的重音引发了一个分布更广泛的N400，其最大值在中央，反映了语义处理中的困难。对于句首音高重音，单词具有更高的F0，但与没有音高重音的句首单词持续时间相同。这些音高重音在400毫秒的时间窗口内引发了一个P200，但没有负性成分。P200由F0峰值的起始潜伏期而非其幅度调制。我们讨论了通过将句首单词的F0与句子中稍后出现的单词的降低的F0进行比较来识别F0峰值的实际出现时，句首重音处理延迟的可能性。
