Donders Institute, Radboud University, 6525EN Nijmegen, The Netherlands, and
Max Planck Institute for Psycholinguistics, 6525XD Nijmegen, The Netherlands.
J Neurosci. 2020 Apr 1;40(14):2914-2924. doi: 10.1523/JNEUROSCI.2271-19.2020. Epub 2020 Feb 28.
The meaning of a sentence can be understood, whether presented in written or spoken form. Therefore, it is highly probable that brain processes supporting language comprehension are at least partly independent of sensory modality. To identify where and when in the brain language processing is independent of sensory modality, we directly compared neuromagnetic brain signals of 200 human subjects (102 males) either reading or listening to sentences. We used multiset canonical correlation analysis to align individual subject data in a way that boosts those aspects of the signal that are common to all, allowing us to capture word-by-word signal variations, consistent across subjects and at a fine temporal scale. Quantifying this consistency in activation across both reading and listening tasks revealed a mostly left-hemispheric cortical network. Areas showing consistent activity patterns included not only areas previously implicated in higher-level language processing, such as left prefrontal, superior and middle temporal areas, and anterior temporal lobe, but also parts of the control network as well as subcentral and more posterior temporal-parietal areas. Activity in this supramodal sentence-processing network starts in temporal areas and rapidly spreads to the other regions involved. The findings indicate not only the involvement of a large network of brain areas in supramodal language processing but also that the linguistic information contained in the unfolding sentences modulates brain activity in a word-specific manner across subjects. The brain can extract meaning from written and spoken messages alike. This requires activity of both brain circuits capable of processing sensory modality-specific aspects of the input signals as well as coordinated brain activity to extract modality-independent meaning from the input. Using traditional methods, it is difficult to disentangle modality-specific activation from modality-independent activation. In this work, we developed and applied a multivariate methodology that allows for a direct quantification of sensory modality-independent brain activity, revealing fast activation of a wide network of brain areas, both including and extending beyond the core network for language.
句子的含义无论是以书面形式还是口头形式呈现，都可以被理解。因此，支持语言理解的大脑过程至少部分独立于感觉模态是极有可能的。为了确定语言处理在大脑中何时以及何处独立于感觉模态，我们直接比较了 200 名人类受试者（102 名男性）在阅读或听句子时的脑磁信号。我们使用多集典型相关分析，以一种增强信号共同部分的方式对齐个体受试者的数据，从而能够捕获跨受试者和精细时间尺度的逐字信号变化。量化跨阅读和听力任务的激活一致性揭示了一个主要的左半球皮质网络。表现出一致活动模式的区域不仅包括先前涉及高级语言处理的区域，如左前额叶、上颞和中颞区域以及前颞叶，还包括控制网络的部分以及中央下和更后颞顶叶区域。这个超模态句子处理网络的活动始于颞区，并迅速扩展到其他涉及的区域。这些发现不仅表明在超模态语言处理中涉及到一个大的脑区网络，而且包含在展开句子中的语言信息以跨受试者的特定方式调制大脑活动。大脑可以从书面和口头信息中提取意义。这需要处理输入信号的感觉模态特定方面的大脑回路的活动，以及协调大脑活动从输入中提取独立于模态的意义。使用传统方法，很难将模态特定的激活与独立于模态的激活区分开来。在这项工作中，我们开发并应用了一种多变量方法，允许直接量化独立于感觉模态的大脑活动，揭示了一个广泛的脑区网络的快速激活，包括但不限于语言的核心网络。
