Speech sound processing within human auditory cortex during self-vocalization

描述（由申请人提供）：在表达性讲话时，来自自身和环境声源的声刺激在听觉系统内不断被处理。这些信息被用来调整和优化语音输出，通过一个特性差的反馈网络。这个网络被认为在包括口吃在内的各种语言障碍中功能失调，并且可能在一些精神病患者中受损。尽管这个神经系统很重要，但人们对人类发声时听觉皮层的功能知之甚少。本课题拟在癫痫手术患者志愿者中采用侵入性实验方法对该系统进行研究。通过直接电生理记录、刺激技术和可逆的焦点冷却，可以获得人类听觉皮层在发声过程中的功能组织信息，而非侵入性方法无法获得这些信息。我的具体目标是：1)识别和描述在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)描述发声过程中听觉反馈的变化如何改变从听觉皮层记录的活动，3)验证额叶语言区域与听觉皮层区域在功能上连接的假设，该假设证明了发声引起的声音处理变化。4)使用皮质冷却方法可逆地使额叶部位失活，并检查这如何影响发声过程中功能连接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计划的背景下进行。幸运的是，我有经验丰富、忠诚的导师，他们是与这个项目相关领域的专家。我也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，这将进一步实现我的目标，即获得成为一名独立神经外科医生所需的科学技能。

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.