Vannuscorps Gilles, Andres Michael, Carneiro Sarah Pereira, Rombaux Elise, Caramazza Alfonso
Harvard University.
Université catholique de Louvain.
J Cogn Neurosci. 2021 Apr;33(4):611-621. doi: 10.1162/jocn_a_01666. Epub 2021 Jan 8.
All it takes is a face-to-face conversation in a noisy environment to realize that viewing a speaker's lip movements contributes to speech comprehension. What are the processes underlying the perception and interpretation of visual speech? Brain areas that control speech production are also recruited during lipreading. This finding raises the possibility that lipreading may be supported, at least to some extent, by a covert unconscious imitation of the observed speech movements in the observer's own speech motor system-a motor simulation. However, whether, and if so to what extent, motor simulation contributes to visual speech interpretation remains unclear. In two experiments, we found that several participants with congenital facial paralysis were as good at lipreading as the control population and performed these tasks in a way that is qualitatively similar to the controls despite severely reduced or even completely absent lip motor representations. Although it remains an open question whether this conclusion generalizes to other experimental conditions and to typically developed participants, these findings considerably narrow the space of hypothesis for a role of motor simulation in lipreading. Beyond its theoretical significance in the field of speech perception, this finding also calls for a re-examination of the more general hypothesis that motor simulation underlies action perception and interpretation developed in the frameworks of motor simulation and mirror neuron hypotheses.
只需在嘈杂环境中进行一次面对面交谈，就能意识到观察说话者的嘴唇动作有助于言语理解。视觉言语感知与解读背后的过程是什么？在唇读过程中，控制言语产生的脑区也会被激活。这一发现增加了一种可能性，即唇读可能至少在一定程度上是由观察者自身言语运动系统对所观察到的言语动作进行隐蔽的无意识模仿——一种运动模拟——所支持的。然而，运动模拟是否以及在多大程度上有助于视觉言语解读仍不清楚。在两项实验中，我们发现，几名先天性面瘫患者的唇读能力与对照组相当，尽管他们的唇部运动表征严重减少甚至完全缺失，但他们完成这些任务的方式在质量上与对照组相似。尽管这一结论是否适用于其他实验条件以及典型发育的参与者仍是一个悬而未决的问题，但这些发现大大缩小了运动模拟在唇读中作用的假设范围。除了言语感知领域，这一发现还呼吁重新审视一个更普遍的假设，即在运动模拟和镜像神经元假设框架中提出的心模拟是动作感知与解读的基础。
