CAS Key Laboratory of Brain Function and Diseases, School of Life Sciences, University of Science and Technology of China, Hefei 230027, China; School of Humanities and Social Sciences, Nanyang Technological University, 637332 Singapore, Singapore.
Neuropsychologia. 2013 Sep;51(11):2238-44. doi: 10.1016/j.neuropsychologia.2013.07.015. Epub 2013 Aug 1.
In Mandarin Chinese, a tonal language, pitch level and pitch contour are two dimensions of lexical tones according to their acoustic features (i.e., pitch patterns). A change in pitch level features a step change whereas that in pitch contour features a continuous variation in voice pitch. Currently, relatively little is known about the hemispheric lateralization for the processing of each dimension. To address this issue, we made whole-head electrical recordings of mismatch negativity in native Chinese speakers in response to the contrast of Chinese lexical tones in each dimension. We found that pre-attentive auditory processing of pitch level was obviously lateralized to the right hemisphere whereas there is a tendency for that of pitch contour to be lateralized to the left. We also found that the brain responded faster to pitch level than to pitch contour at a pre-attentive stage. These results indicate that the hemispheric lateralization for early auditory processing of lexical tones depends on the pitch level and pitch contour, and suggest an underlying inter-hemispheric interactive mechanism for the processing.
在汉语普通话中，音高和音高轮廓是根据其声学特征（即音高模式）划分的两个声调维度。音高水平的变化表现为阶跃变化，而音高轮廓的变化则表现为音高的连续变化。目前，对于每个维度的处理的半球侧化相对知之甚少。为了解决这个问题，我们对母语为汉语的人进行了全头电记录，以响应每个维度的汉语声调对比。我们发现，对音高水平的非注意听觉加工明显偏向于右半球，而对音高轮廓的加工则偏向于左半球。我们还发现，在非注意阶段，大脑对音高水平的反应比对音高轮廓的反应更快。这些结果表明，声调的早期听觉加工的半球侧化取决于音高水平和音高轮廓，并暗示了处理过程中存在一种潜在的半球间交互机制。
