Speech sound processing within human auditory cortex during self-vocalization

描述(申请人提供)：在富于表现力的讲话中，来自自身和环境声源的声刺激在听觉系统内不断地被处理。这些信息被用来通过特征不佳的反馈网络来调整和优化语音输出。这一网络被认为在包括口吃在内的各种言语障碍中存在功能障碍，在一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质的功能知之甚少。在这项建议中，我计划用侵入性实验方法研究这一系统在癫痫手术患者志愿者中的应用。通过使用直接电生理记录、刺激技术和可逆局灶冷技术，可以获得发声过程中人类听觉皮质功能组织的信息，而这些信息是非侵入性方法无法获得的。我的具体目标是1)识别和表征发声过程中记录的听觉诱发反应的差异，以及当这些发声被回放时，2)表征发声过程中听觉反馈变化如何改变从听觉皮质记录的活动，3)测试额叶言语区域在功能上与听觉皮质场相连的假设，这展示了发声诱导的声音处理变化，以及4)使用皮质降温方法可逆地使额叶部位失活，并研究这如何影响发声过程中功能相连的颞叶部位的语音处理。这项研究将在一个全面的职业发展方案的背景下进行。我很幸运，有经验和承诺的导师谁是专家在这个项目的相关领域。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、指导学习和研讨会，这将促进我获得成为一名独立神经外科医生-科学家所必需的科学技能的目标。 相关性：这个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，在某些言语障碍和精神病患者中可能会出现异常。

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.