Laboratory of Experimental Psychology & Neuroscience, Institute of Cognitive Neurology (INECO), Buenos Aires, Capital Federal, Argentina.
PLoS One. 2010 Jul 28;5(7):e11751. doi: 10.1371/journal.pone.0011751.
Behavioral studies have provided evidence for an action-sentence compatibility effect (ACE) that suggests a coupling of motor mechanisms and action-sentence comprehension. When both processes are concurrent, the action sentence primes the actual movement, and simultaneously, the action affects comprehension. The aim of the present study was to investigate brain markers of bidirectional impact of language comprehension and motor processes.
METHODOLOGY/PRINCIPAL FINDINGS: Participants listened to sentences describing an action that involved an open hand, a closed hand, or no manual action. Each participant was asked to press a button to indicate his/her understanding of the sentence. Each participant was assigned a hand-shape, either closed or open, which had to be used to activate the button. There were two groups (depending on the assigned hand-shape) and three categories (compatible, incompatible and neutral) defined according to the compatibility between the response and the sentence. ACEs were found in both groups. Brain markers of semantic processing exhibited an N400-like component around the Cz electrode position. This component distinguishes between compatible and incompatible, with a greater negative deflection for incompatible. Motor response elicited a motor potential (MP) and a re-afferent potential (RAP), which are both enhanced in the compatible condition.
CONCLUSIONS/SIGNIFICANCE: The present findings provide the first ACE cortical measurements of semantic processing and the motor response. N400-like effects suggest that incompatibility with motor processes interferes in sentence comprehension in a semantic fashion. Modulation of motor potentials (MP and RAP) revealed a multimodal semantic facilitation of the motor response. Both results provide neural evidence of an action-sentence bidirectional relationship. Our results suggest that ACE is not an epiphenomenal post-sentence comprehension process. In contrast, motor-language integration occurring during the verb onset supports a genuine and ongoing brain motor-language interaction.
行为研究为动作-句子兼容性效应（ACE）提供了证据，该效应表明运动机制与动作-句子理解之间存在耦合。当这两个过程同时发生时，动作句子会启动实际动作，同时，动作会影响理解。本研究旨在探讨语言理解和运动过程相互影响的脑标记物。
方法/主要发现：参与者听描述涉及张开的手、握拳或无手部动作的句子。每个参与者都被要求按下按钮以表示他/她对句子的理解。每个参与者都被分配了一种手形，要么是闭合的，要么是张开的，必须用这种手形来激活按钮。根据反应和句子之间的兼容性，有两个组（取决于分配的手形）和三个类别（兼容、不兼容和中性）。在这两个组中都发现了 ACE。语义处理的脑标记物在 Cz 电极位置显示出 N400 样成分。该成分区分兼容和不兼容，不兼容时的负偏置更大。运动反应引起运动电位（MP）和再传入电位（RAP），这两种电位在兼容条件下都增强。
结论/意义：本研究结果提供了语义处理和运动反应的 ACE 皮质测量的第一个结果。N400 样效应表明，与运动过程不兼容会以语义方式干扰句子理解。运动电位（MP 和 RAP）的调制揭示了运动反应的多模态语义促进。这两个结果都为动作-句子的双向关系提供了神经证据。我们的结果表明，ACE 不是句子理解后的一个附加过程。相反，动词起始时的运动-语言整合支持大脑运动-语言相互作用的真实和持续存在。
