Cognitive and Affective Neuroscience Unit, University of Zurich, 8050 Zurich, Switzerland.
Neuroscience Center Zurich, University of Zurich and ETH Zurich, 8050 Zurich, Switzerland.
Cereb Cortex. 2023 Feb 7;33(4):1170-1185. doi: 10.1093/cercor/bhac128.
Voice signaling is integral to human communication, and a cortical voice area seemed to support the discrimination of voices from other auditory objects. This large cortical voice area in the auditory cortex (AC) was suggested to process voices selectively, but its functional differentiation remained elusive. We used neuroimaging while humans processed voices and nonvoice sounds, and artificial sounds that mimicked certain voice sound features. First and surprisingly, specific auditory cortical voice processing beyond basic acoustic sound analyses is only supported by a very small portion of the originally described voice area in higher-order AC located centrally in superior Te3. Second, besides this core voice processing area, large parts of the remaining voice area in low- and higher-order AC only accessorily process voices and might primarily pick up nonspecific psychoacoustic differences between voices and nonvoices. Third, a specific subfield of low-order AC seems to specifically decode acoustic sound features that are relevant but not exclusive for voice detection. Taken together, the previously defined voice area might have been overestimated since cortical support for human voice processing seems rather restricted. Cortical voice processing also seems to be functionally more diverse and embedded in broader functional principles of the human auditory system.
语音信号是人类交流的重要组成部分，大脑中的一个皮质语音区似乎支持对声音与其他听觉对象的区分。该听觉皮层（AC）中的这个大型皮质语音区被认为具有选择性处理语音的功能，但它的功能分化仍然难以捉摸。我们在人类处理语音和非语音声音、以及模仿某些语音特征的人工声音时使用了神经影像学技术。首先，令人惊讶的是，最初描述的位于高级 Te3 中央的高级 AC 中的语音区的一小部分，而不是整个区域，才具有超越基本声学声音分析的特定听觉皮质语音处理能力。其次，除了这个核心语音处理区域之外，低阶和高阶 AC 中剩余的大部分语音区仅辅助性地处理语音，并且可能主要捕捉到语音和非语音之间的非特异性心理声学差异。第三，低阶 AC 的一个特定亚区似乎专门解码与语音检测相关但不专用于语音检测的声学声音特征。综上所述，之前定义的语音区可能被高估了，因为人类语音处理的皮质支持似乎相当有限。皮质语音处理的功能似乎也更加多样化，并嵌入到人类听觉系统更广泛的功能原理中。
