Cortical Dynamics Underlying Interactive Language Use

项目概要/摘要 本研究旨在探讨口语表达中话语规划的神经机制 交互.我们假设，大脑皮层特定部位的计划相关活动， 流利的人类对话所必需的交流。为了验证这一假设，我们将确定规划区域 使用皮层电图（ECoG），一种具有足够时间和空间精度的技术， 神经反应的主体参与控制的互动和非结构化的对话。在 根据初步数据，我们发现额下回（IFG;包含布罗卡区）的活动通常是 与话语规划有关。我们将通过分离语言处理和大脑皮层反应来描述皮层脑电反应的特征。 以及语音输出缓冲器（即，工作记忆）的组成部分。然后我们将决定 计划相关活动的重要性，通过检查行为的影响，从补充 可逆的皮质扰动 在目标1中，我们将使用ECoG来验证我们的假设，即特定的皮层部位参与了语音选择性 在两种受控交互中的运动规划（即，一个问答范例）以及自然， 与人类行为学相关的谈话 在目标2中，我们将使用两种不同的方法将话语规划分解为它的组成部分：（1） “命令-反应”范式与言语的相关性增加（与其他运动行为相反）， 确定这些反应可以被描述为语言处理的程度，以及（2） 可变延迟图片命名任务，以隔离观察到的语音输出缓冲成分 规划活动。 在目标3中，我们将通过测量 在规划区域的短暂扰动之后发生的行为缺陷。直接电刺激大鼠 将被用来破坏具有高时间精度的规划活动。轻度局灶性脑表面冷却将 作为一种补充的方法，调制规划活动的时间动态。 从我们的研究中，我们将研究使声音相互作用能够更好地理解的皮层网络。 神经机制的基础轮流与更广泛的目标，告知未来的治疗 旨在解决影响人类社会语言使用的临床条件的干预措施。

Project Summary/Abstract This project will investigate the neural mechanisms underlying utterance planning in the service of spoken interactions. We hypothesize that planning-related activity within specific cortical sites enables the rapid vocal exchanges necessary for fluent human conversation. To test this hypothesis, we will identify planning regions using electrocorticography (ECoG), a technique with sufficient temporal and spatial precision to localize neural responses in subjects engaged in both controlled interactions and unstructured conversation. In preliminary data, we found that activity within the inferior frontal gyrus (IFG; containing Broca’s region) is often tied to utterance planning. We will characterize ECoG responses by isolating both the linguistic processing and phonological output buffer (i.e., working memory) components of these responses. We will then determine the importance of planning-related activity by examining behavioral effects that result from complementary reversible cortical perturbations. In Aim 1, we will use ECoG to test our hypothesis that specific cortical sites are involved in speech-selective motor planning in both controlled interactions (i.e., a question-answer paradigm) as well as natural, ethologically-relevant conversation. In Aim 2, we will dissect utterance planning into its component parts using two different approaches: (1) a ‘command-response’ paradigm with increasing relevance to speech (as opposed to other motor acts) to determine the degree to which these responses can be characterized as linguistic processing and (2) a variable delay picture naming task to isolate the phonological output buffering component of the observed planning activity. In Aim 3, we will assess the necessity of planning-related activity for vocal interactions by measuring the behavioral deficits that occur following transient perturbations of planning regions. Direct cortical stimulation will be used to disrupt planning activity with high temporal precision. Mild focal brain surface cooling will be used as a complementary method of modulating the temporal dynamics of planning activity. From our studies, we will investigate the cortical network enabling vocal interactions to better understand the neural mechanisms underlying turn-taking with the broader goal of informing future therapeutic interventions designed to address the clinical conditions affecting human social language use.