Human Auditory Cortex Physiology

描述(申请人提供)：语音是我们听到的最重要的声音；然而，关于这些刺激是如何通过人类听觉皮质内的神经活动表现出来的，我们知之甚少。我们研究的目标是了解人类大脑皮层中负责声音处理的区域的功能组织和联系，并研究听觉语言刺激在这些区域是如何呈现的。这些实验包括将解剖学和功能磁共振方法与清醒状态下的直接皮质电生理记录和电刺激技术相结合，表现为接受顽固性癫痫临床评估的受试者。我们将通过测试一系列具体的假设来实现我们的目标：(1)听觉皮层区域的位置和功能特性；(2)对语音刺激的诱发反应在这些区域内的表现和转换方式；以及(3)这些区域之间的功能联系和信息流模式。这些目标是由一个经验丰富的多学科团队使用非侵入性MRI和直接调查方法的组合来实现的，以便在相同的实验对象中收集互补的人体生理和解剖学数据集。这些数据不能单独使用非侵入性方法获得，这种多模式实验方法旨在克服目前阻碍该领域研究进展的重大障碍。据我们所知，如果我们的目标得以实现，由此产生的数据将是第一个直接展示当受试者从事心理物理语音处理任务时，在上颞平面和外侧颞上回的多个生理定义的听觉区域内的神经活动如何表示声学和语音语音信息的数据。我们追求这些研究目标，相信对正常人类听觉系统的基本结构和功能的了解对于理解听力、言语和语言各方面损害的机制是必不可少的。 公共卫生相关性：这项研究计划产生了关于人类听觉皮质功能组织的独特信息，这些信息是使用替代的非侵入性方法无法获得的。从这些研究中获得的知识将为语音信息如何在人脑中呈现提供新的见解，并有助于为受广泛沟通障碍影响的患者合理设计新的治疗和康复策略。

DESCRIPTION (provided by applicant): Speech sounds are the most important sounds that we hear; yet little is known about how these stimuli are represented by neural activity within human auditory cortex. The goal of our research is to understand the functional organization and connections of those areas of human cerebral cortex that are engaged in sound processing and examine how auditory speech stimuli are represented in these regions. These experiments involve combining anatomical and functional MRI methods with direct cortical electrophysiological recordings and electrical stimulation techniques in awake, behaving human subjects undergoing clinical evaluation of intractable epilepsy. We will pursue our goals by testing a series of specific hypotheses regarding: (1) the locations and functional properties of auditory cortical fields; (2) the manner in which evoked responses to speech stimuli are represented and transformed within these fields; and (3) the functional connections and patterns of information flow between these fields. These objectives are pursued by an experienced multidisciplinary team using combinations of non-invasive MRI and direct investigative methods in order to gather complementary sets of human physiological and anatomical data in the same experimental subjects. These data cannot be obtained using non-invasive methods alone, and this multi-modal experimental approach is designed to overcome significant barriers that currently impede research progress in this field. To our knowledge, if our objectives are achieved, the resulting data will be the first of its kind demonstrating directly how acoustic and phonetic speech information is represented by neural activity within multiple physiologically-defined auditory fields of the superior temporal plane and lateral superior temporal gyrus as subjects engage in psychophysical speech-processing tasks. We pursue these research objectives believing that knowledge of the fundamental structure and function of the normal human auditory system is essential to understanding mechanism that underlie impairment of all aspects of hearing, speech, and language. PUBLIC HEALTH RELEVANCE: This research program generates unique information about the functional organization of human auditory cortex that cannot be obtained using alternative, non-invasive approaches. Knowledge gained from these studies will provide new insights into how speech information is represented within the human brain and aid in the rational design of new therapeutic and rehabilitation strategies for patients affected by a wide range of communication disorders.