Cortical Dynamics Underlying Interactive Language Use

项目概要/摘要 该项目将研究为口语服务的话语规划的神经机制 互动。我们假设特定皮质部位内与计划相关的活动能够使快速发声 流利的人类对话所必需的交流。为了检验这个假设，我们将确定规划区域 使用皮层电图描记术 (ECoG)，这是一种具有足够时间和空间精度的技术来定位 参与受控互动和非结构化对话的受试者的神经反应。在 根据初步数据，我们发现额下回（IFG；包含布罗卡区）内的活动通常是 与言语规划相关。我们将通过分离语言处理来描述 ECoG 反应的特征 这些响应的语音输出缓冲区（即工作记忆）组件。然后我们将确定 通过检查互补性行为所产生的行为影响来认识规划相关活动的重要性 可逆的皮质扰动。 在目标 1 中，我们将使用 ECoG 来检验我们的假设，即特定皮层位点参与言语选择性 受控交互（即问答范式）以及自然交互中的运动规划， 与行为学相关的对话。 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其组成部分：(1) “命令-响应”范式与言语（相对于其他运动行为）的相关性越来越大 确定这些反应可以被表征为语言处理的程度，并且（2） 可变延迟图片命名任务，以隔离观察到的语音输出缓冲组件 规划活动。 在目标 3 中，我们将通过测量声音互动来评估规划相关活动的必要性。 规划区域短暂扰动后发生的行为缺陷。直接皮质刺激 将用于以高时间精度扰乱计划活动。轻度局部脑表面冷却将 用作调节规划活动的时间动态的补充方法。 根据我们的研究，我们将研究使声音交互能够更好地理解的皮质网络 轮流背后的神经机制，其更广泛的目标是为未来的治疗提供信息 旨在解决影响人类社会语言使用的临床状况的干预措施。

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.