近日，加拿大麦吉尔大学Philippe Albouy等研究人员揭示出语言和旋律的大脑不对称性机制。该项研究成果发表在2020年2月28日出版的《科学》上。

语言和音乐的大脑不对称性是否来自听觉提示或特定领域的神经网络？研究人员选择性地过滤了歌唱语音刺激中的时间或频谱调制，对于这些调制而言，语言和旋律内容是相互交叉和平衡的。语言的感知仅随着时间信息的退化而降低，而旋律的感知仅随着频谱的退化而降低。

功能性磁共振成像数据表明，语言和旋律的神经解码分别取决于左、右听觉区域的活动模式。对每个区域内的频谱时间调制速率的特定敏感性支持了这种不对称性。最后，退化对知觉的影响与其对神经分类的影响互不干扰。

这些结果表明，交流信号的声学特性与适应该目的的神经特化之间存在匹配。

附：英文原文

Title: Distinct sensitivity to spectrotemporal modulation supports brain asymmetry for speech and melody

Author: Philippe Albouy, Lucas Benjamin, Benjamin Morillon, Robert J. Zatorre

Issue&Volume: 2020/02/28

Abstract: AbstractDoes brain asymmetry for speech and music emerge from acoustical cues or from domain-specific neural networks We selectively filtered temporal or spectral modulations in sung speech stimuli for which verbal and melodic content was crossed and balanced. Perception of speech decreased only with degradation of temporal information, whereas perception of melodies decreased only with spectral degradation. Functional magnetic resonance imaging data showed that the neural decoding of speech and melodies depends on activity patterns in left and right auditory regions, respectively. This asymmetry is supported by specific sensitivity to spectrotemporal modulation rates within each region. Finally, the effects of degradation on perception were paralleled by their effects on neural classification. Our results suggest a match between acoustical properties of communicative signals and neural specializations adapted to that purpose.

DOI: 10.1126/science.aaz3468

Source: https://science.sciencemag.org/content/367/6481/1043