Electrophysiological Approaches to Understanding Functional Organization of Speech in the Brain

摘要 为了理解语音，人脑必须解析嘈杂的声音信号并将其转换为有意义的信号 语言内容，包括音素、音节、单词和句子。这涉及到确定时间 重要的声音事件，例如句子或短语的开始。在检测到这些发作后， 必须确定句子的内容。颞上回 (pSTG)——包括 经典的“韦尼克区”——对于这一过程至关重要，但直到最近，人们对其功能知之甚少 组织，特别是这个职能组织在整个开发过程中如何变化。我们最近的 研究表明，pSTG 的空间离散区域对于指示句子或短语何时至关重要 开始。该区域在空间和功能上与更前面的“持续”区域不同，这些区域编码 整个句子的语音特征信息。从功能上讲，后发性和前持续性 区域分别表现出短和长的时间整合时间，表明在 自然语音处理。在这里，我们提出了一种使用稀有数据集的创新方法，其中神经活动 直接从儿科患者参与者的人类听觉皮层和言语相关区域记录 正在进行癫痫手术的临床评估。该方法克服了空间和时间分辨率 克服了其他非侵入性手术的局限性，并为了解人类听觉功能提供了一个难得的窗口 皮质。拟议的研究将使用高分辨率颅内记录来研究大脑如何检测 自然语音混合物中的声学起始，以及对这些声音的神经生理学反应 从幼儿期到青春期的转变。此外，我们将研究这些对发作的反应如何 受环境的调节，包括注意力期间和自我产生的声音。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，这项研究对于语音脑计算机的发展具有重要意义 界面。我们的结果还可以告诉人们如何在自然环境中处理语音和语言，这已经 对治疗发育性语言障碍、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.