Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, 94720, CA, USA.
Departments of Neuroscience and Computer Science, University of Texas, Austin, Austin, 78712, TX, USA.
Nat Commun. 2023 Jul 18;14(1):4309. doi: 10.1038/s41467-023-39872-w.
Speech processing requires extracting meaning from acoustic patterns using a set of intermediate representations based on a dynamic segmentation of the speech stream. Using whole brain mapping obtained in fMRI, we investigate the locus of cortical phonemic processing not only for single phonemes but also for short combinations made of diphones and triphones. We find that phonemic processing areas are much larger than previously described: they include not only the classical areas in the dorsal superior temporal gyrus but also a larger region in the lateral temporal cortex where diphone features are best represented. These identified phonemic regions overlap with the lexical retrieval region, but we show that short word retrieval is not sufficient to explain the observed responses to diphones. Behavioral studies have shown that phonemic processing and lexical retrieval are intertwined. Here, we also have identified candidate regions within the speech cortical network where this joint processing occurs.
语音处理需要使用基于语音流动态分割的一组中间表示来从声学模式中提取意义。我们使用 fMRI 获得的全脑图谱，不仅研究了单个音素的皮质音素处理位置，还研究了由双音和三音组成的短组合的音素处理位置。我们发现，音素处理区域比以前描述的要大得多：它们不仅包括背侧上颞回的经典区域，还包括外侧颞叶皮层中双音特征最佳表示的更大区域。这些确定的音素区域与词汇检索区域重叠，但我们表明，短词检索不足以解释对双音的观察反应。行为研究表明，音素处理和词汇检索是交织在一起的。在这里，我们还在语音皮质网络中确定了发生这种联合处理的候选区域。
