Catagorizing Parallel Human Auditory Pathways by Spatiotemporally Focused TMS

描述（由申请人提供）：人脑以惊人的速度和轻松解释复杂的声学环境。虽然在过去的几十年里，我们对声音处理的神经元基础的理解已经有了很大的进步，但人脑皮层听觉通路的平行功能组织仍然是难以捉摸的。该提案旨在通过检查声音信息的空间（“在哪里”）与身份（“什么”）的双通路的理论模型，开发，测试和完善一种新的实验方法来映射平行的听觉通路。我们的新方法结合了先进的时空脑成像技术和短暂非侵入性失活期间的行为测量（即，“瞬时损伤”）。我们将利用解剖学和功能性MRI，EEG和脑磁图（MEG）来确定在声音识别（“什么”）和定位（“哪里”）任务期间大脑活动的位置和时间过程。经颅磁刺激（TMS）将用于调节在任务执行期间激活的听觉皮层的各个区域。这将使我们能够调查是否时空集中在假定的平行听觉通路的瞬时失活的结果在行为效应的双重分离。我们将同时测量脑电和经颅磁刺激，以研究不同听觉皮层区域的瞬时失活对听觉诱发反应的调制。 拟议中的研究将使用先进的神经成像方法来研究人类大脑如何处理听觉信息。时空聚焦的TMS方法将解剖学上和时间上聚焦的干扰脉冲非侵入性地且完全安全地应用到人脑中。干扰的解剖学和时间焦点将从时空脑成像电影中获得，基于组合的fMRI/MEG/EEG。这种多模式的方法使我们能够测试在皮层听觉通路的不同焦点的瞬时失活的特定行为效应，提供了一种独特的方式来验证动物模型，人类病变研究和神经影像学研究所提出的理论。我们的研究将有助于更好地了解人类大脑中处理声音信息的神经通路和回路。虽然我们目前的重点是基础研究，但对听觉感知的神经基础的更深入了解可能最终有利于听力障碍和学习障碍的调查，以及助听器和假肢的开发。 公共卫生相关性：我们使用先进的大脑成像和行为方法来映射人类的平行皮层听觉通路，通过专门测试不同的“什么”和“哪里”流的假设。这项研究也可能推进对各种听觉异常疾病的调查。

DESCRIPTION (provided by applicant): The human brain interprets complex acoustic environments with astounding speed and ease. Although our understanding on the neuronal basis of sound processing has greatly advanced during the past decades, the parallel functional organization of cortical auditory pathways of the human brain is still elusive. This proposal aims to develop, test, and refine a new experimental approach for mapping parallel auditory pathways, by examining a theoretical model of dual pathways for spatial ("where") vs. identity ("what") of sound information. Our novel approach combines advanced spatiotemporal brain imaging techniques and behavioral measurements during transient non-invasive deactivation (i.e., "transient lesions") of individual regions of human auditory pathway. We will utilize anatomical and functional MRI, EEG, and magnetoencephalography (MEG) to identify the locations and time courses of brain activity during sound identification ("what") and localization ("where") tasks. Transcranial magnetic stimulation (TMS) will be utilized to modulate individual regions of auditory cortex that are activated during task performance. This will allow us to investigate whether spatiotemporally focused transient deactivations in the putative parallel auditory pathways result in a double dissociation of behavioral effects. We will measure EEG simultaneously with TMS, to investigate modulation of auditory evoked responses by transient deactivation of different auditory cortex areas. The proposed studies will use advanced neuroimaging methods to study how the human brain processes auditory information. The spatiotemporally focused TMS approach applies anatomically and temporally focused interference pulses non-invasively and completely safely into the human brain. The anatomical and temporal foci of interference will be obtained from spatiotemporal brain imaging movies, based on combined fMRI/MEG/EEG. This multimodal approach allows us to test the specific behavioral effects of transient deactivation in the different foci of cortical auditory pathway, providing a unique way to verify theories suggested by animal models, human lesion studies, and neuroimaging research. Our research will lead to a better understanding of the neuronal pathways and circuits involved in the processing of sound information in the human brain. Although our current focus is in basic research, greater understanding of the neuronal basis of auditory perception may ultimately benefit investigation of hearing impairments and learning disabilities, as well as development of hearing aids and prosthetics. PUBLIC HEALTH RELEVANCE: We use advanced brain imaging and behavioral methods for mapping of parallel cortical auditory pathways in humans, by specifically testing a hypothesis of distinct "what" and "where" streams. This research may also advance investigation of various disorders with auditory abnormalities.