Speech sound processing within human auditory cortex during self-vocalization

描述（由申请人提供）：在表达性言语过程中，来自自身产生的声源和环境声源的声刺激在听觉系统内不断被处理。该信息用于通过特征较差的反馈网络来调整和优化语音输出。该网络被认为在多种言语障碍（包括口吃）中出现功能障碍，并且在某些精神病患者中可能会受到损害。尽管这种神经系统很重要，但人们对人类发声时听觉皮层如何发挥作用却知之甚少。在这个提案中，我计划在癫痫手术患者志愿者中使用侵入性实验方法来研究这个系统。通过使用直接电生理记录、刺激技术和可逆局灶冷却，可以获得有关发声过程中人类听觉皮层功能组织的信息，这是使用非侵入性方法无法获得的。我的具体目标是 1) 识别和表征发声期间记录的听觉诱发反应的差异以及这些发声回放时的差异，2) 表征发声过程中听觉反馈的变化如何改变听觉皮层记录的活动，3) 测试额叶言语区域与听觉皮层区域功能性连接的假设，该听觉皮层区域证明发声引起的声音处理变化，4) 使用皮层冷却方法可逆地停用额叶部位并研究如何这会影响发声期间功能连接的颞叶部位的语音处理。这项研究将在综合职业发展计划的背景下进行。我很幸运拥有经验丰富且忠诚的导师，他们是与该项目相关领域的专家。我还将完全获得进行人脑生理学研究所需的最佳资源。我将参加正式的课程、定向学习和研讨会，这将进一步推动我获得成为一名独立的神经外科医生科学家所需的科学技能的目标。 相关性：该项目将进一步加深我们对人类发声所涉及的大脑机制的理解。人们对这些机制知之甚少，并且在某些言语障碍和精神病中可能会出现异常。

DESCRIPTION (provided by applicant): During expressive speech, acoustic stimuli from both self-generated and environmental sound sources are continually processed within the auditory system. This information is used to adjust and optimize speech output through a poorly characterized feedback network. This network is thought to be dysfunctional in a variety of speech disorders, including stuttering, and may be impaired in some patients with psychoses. Despite the importance of this neural system, little is known about how auditory cortex functions when humans vocalize. In this proposal I plan to study this system using invasive experimental methods in epilepsy surgery patient volunteers. By using direct electrophysiologic recording, stimulation techniques, and reversible focal cooling, it is feasible to obtain information about the functional organization of human auditory cortex during vocalization that cannot be obtained using non-invasive methods. My specific aims are to 1) identify and characterize differences in auditory evoked responses recorded during vocalization and when these vocalizations are played back, 2) characterize how auditory feedback alterations during vocalization changes activity recorded from auditory cortex, 3) test the hypothesis that frontal lobe speech areas are functionally connected to the auditory cortical fields that demonstrate vocalization-induced changes in sound processing, and 4) use a cortical cooling method to reversibly deactivate frontal lobe sites and examine how this affects speech sound processing in functionally connected temporal lobe sites during vocalization. This research will be carried out in the context of a comprehensive career development program. I am fortunate to have experienced and committed mentors who are experts in areas relevant to this project. I also will have full access to the optimal resources needed for conducting human brain physiology research. I will participate in formal coursework, directed study and seminars that will further my objective of acquiring the scientific skills necessary to become an independent neurosurgeon-scientist. RELEVANCE: This project will further our understanding of brain mechanisms involved in human vocalization. These mechanisms are poorly understood and may be abnormal in certain speech disorders and psychoses.