Electrophysiological Approaches to Understanding Functional Organization of Speech in the Brain

摘要 为了理解语音，人脑必须解析并将嘈杂的声学信号转换为有意义的 语言内容，包括音素、音节、单词和句子。这涉及到确定 重要的声学事件，如句子或短语的开始。在检测到这些发作后， 必须确定判决的内容。后上级颞回（pSTG）-包括 经典的“韦尼克区”-是至关重要的这一过程，但直到最近，很少有人知道它的功能 组织，特别是这个功能组织在整个开发过程中如何变化。我们最近 一项研究表明，pSTG的空间离散区域对于指示句子或短语何时出现是至关重要的。 开始.这个区域在空间和功能上都不同于更前部的“持续”区域， 语音特征信息贯穿整个句子。在功能上，后发作和前持续 区域分别显示短和长的时间整合时间，这表明互补的作用， 自然语音处理在这里，我们提出了一种创新的方法，使用罕见的数据集， 直接从儿童患者参与者的人类听觉皮层和语音相关区域记录 正在接受癫痫手术的临床评估该方法克服了空间和时间分辨率 其他非侵入性手术的局限性，并提供了一个罕见的窗口，人类听觉功能 皮层这项拟议中的研究将使用高分辨率颅内记录来研究大脑如何检测 自然语音声音混合物中的声学起始，以及神经生理学对这些声音的反应 从幼儿期到青春期的变化。此外，我们将研究这些反应如何发作， 是由上下文调制的，包括在注意力和自发的声音。除了提供 深入了解人类听觉皮层的基本功能组织和听觉的皮层机制 场景分析，该研究对开发语音脑计算机具有重要意义 接口.我们的研究结果还可以告知语音和语言在自然环境中是如何处理的， 对发展性语言障碍、听觉处理障碍、阅读障碍、 自闭症和失语症。

ABSTRACT To understand speech, the human brain must parse and transform a noisy acoustic signal into meaningful linguistic content, including phonemes, syllables, words, and sentences. This involves determining the timing of important acoustic events, such as the onset of a sentence or a phrase. Following detection of these onsets, the content of the sentence must be determined. The posterior superior temporal gyrus (pSTG)—including the classic “Wernicke’s area”—is critical to this process, but until recently, little was known about its functional organization, and in particular how this functional organization changes throughout development. Our recent work showed that a spatially discrete region of the pSTG is critical for indicating when a sentence or phrase begins. This region is distinct spatially and functionally from more anterior “sustained” areas that encode phonetic feature information throughout a sentence. Functionally, both posterior onset and anterior sustained regions show short and long temporal integration times, respectively, suggesting complimentary roles in natural speech processing. Here, we propose an innovative approach using rare datasets where neural activity is recorded directly from the human auditory cortex and speech-related areas in pediatric patient participants undergoing clinical evaluation for epilepsy surgery. This method overcomes the spatial and temporal resolution limitations of other noninvasive procedures, and provides a rare window into the function of the human auditory cortex. The proposed study will use high resolution intracranial recordings to investigate how the brain detects acoustic onsets in natural speech sound mixtures, and how neurophysiological responses to these sounds change from early childhood to adolescence. Furthermore, we will investigate how these responses to onsets are modulated by context, including during attention and for self-generated sounds. In addition to providing insight into the basic functional organization of the human auditory cortex and cortical mechanisms for auditory scene analysis, this research has important implications for the development of a speech brain computer interface. Our results could also inform how speech and language are processed in natural contexts, which has implications for the treatment of developmental language disorders, auditory processing disorder, dyslexia, autism, and aphasia.