Department of Speech Hearing and Phonetic Sciences, University College London, London WC1N 1PJ, UK.
Department of Psychology, Edge Hill University, Ormskirk, L39 4QP, UK.
Philos Trans R Soc Lond B Biol Sci. 2021 Dec 20;376(1840):20200392. doi: 10.1098/rstb.2020.0392. Epub 2021 Nov 1.
Humans are vocal modulators par excellence. This ability is supported in part by the dual representation of the laryngeal muscles in the motor cortex. Movement, however, is not the product of motor cortex alone but of a broader motor network. This network consists of brain regions that contain somatotopic maps that parallel the organization in motor cortex. We therefore present a novel hypothesis that the dual laryngeal representation is repeated throughout the broader motor network. In support of the hypothesis, we review existing literature that demonstrates the existence of network-wide somatotopy and present initial evidence for the hypothesis' plausibility. Understanding how this uniquely human phenotype in motor cortex interacts with broader brain networks is an important step toward understanding how humans evolved the ability to speak. We further suggest that this system may provide a means to study how individual components of the nervous system evolved within the context of neuronal networks. This article is part of the theme issue 'Voice modulation: from origin and mechanism to social impact (Part I)'.
人类是卓越的发声调节者。这种能力部分依赖于喉肌在运动皮层中的双重代表。然而，运动不仅仅是运动皮层的产物，而是更广泛的运动网络的产物。该网络由包含与运动皮层组织平行的躯体定位图的脑区组成。因此，我们提出了一个新的假设，即双重喉肌代表在更广泛的运动网络中重复出现。为了支持这一假设，我们回顾了现有的文献，这些文献证明了网络范围内存在躯体定位，并初步为这一假设的合理性提供了证据。了解运动皮层中这种独特的人类表型如何与更广泛的大脑网络相互作用，是理解人类如何进化出说话能力的重要一步。我们进一步提出，这个系统可能为研究神经系统的各个组成部分如何在神经元网络的背景下进化提供了一种方法。本文是主题为“声音调制：起源、机制与社会影响（第一部分）”的一部分。
