Auditory & Integrative Processes in Prefrontal Cortex

听觉和视觉刺激的整合对于通过视觉和声音识别物体、有效沟通以及在我们复杂的世界中导航至关重要。虽然目前还不清楚大脑中来自这两种模式的信息在哪里被结合和处理以控制特定的行为，但额叶已被确定为与记忆和语言相关的区域，这依赖于交叉感觉整合。此外，最近对猕猴前额叶皮层的下凸性（IFC）的分析表明，视觉和听觉处理的区域并列和重叠，表明可能在多模态感觉整合中起作用。先前对前额叶皮层的研究主要集中在它在视觉记忆处理中的作用。这个项目的目标是获得对额叶如何处理复杂的听觉、视觉和组合刺激的基本理解，这些刺激有助于有意义的交流和物体识别。我们的实验将着重于猕猴IFC的神经生理学和解剖学分析。具体而言，实验将表征国际金融中心内听觉和视觉反应的选择性、特异性和组织。此外，我们将确定IFC内的听觉或视觉反应神经元是否实际上是多模态的（即对视觉和听觉联合刺激作出反应）。此外，我们将比较单位响应调制多模态刺激呈现被动或联想记忆任务。最后，我们将通过确定IFC生理特征区域的解剖连接来阐明额叶中听觉、视觉和多模态反应的神经回路。本研究的发现将有助于揭示与语音感知相关的通信过程的电路和细胞机制。我们的发现也将对理解影响沟通和语言的神经系统疾病有启示，包括精神分裂症和自闭症，这些疾病的功能障碍与额叶有关。

The integration of auditory and visual stimuli is crucial for recognizing objects by sight and sound, communicating effectively, and navigating through our complex world. While it is not clear where in the brain information from these two modalities are combined and processed to govern specific behaviors, the frontal lobes have been identified as a region associated with memory and language, which depend on cross- sensory integration. Moreover, recent analysis of the inferior convexity (IFC) of the prefrontal cortex in the macaque monkey has revealed juxtaposed and overlapping areas of visual and auditory processing, indicating a possible role in multimodal sensory integration. Previous research on the prefrontal cortex has focused on its role in visual memory processing. The goal of this project is to obtain a fundamental understanding of how the frontal lobes process complex auditory, visual and combined stimuli which serve meaningful communication and object recognition. Our experiments will focus on the neurophysiological and anatomical analysis of the IFC in the macaque monkey. Specifically, experiments will characterize the selectivity, specificity and organization of auditory and visual responses within the IFC. In addition, we will ascertain whether auditory or visual responsive neurons within the IFC are, in fact, multimodal (i.e. respond to combined visual and auditory stimuli). Moreover we will compare the modulation of unit responsiveness to multimodal stimuli presented passively or in an associative memory task. Finally, we will elucidate the neuronal circuitry underlying auditory, visual and multimodal responses in the frontal lobes by determining the anatomical connections of physiologically characterized regions of the IFC. Findings from the present study will help to reveal the circuitry and cellular mechanisms underlying communication processes relevant to speech perception. Our findings will also have implications for understanding neurological disorders which affect communication and language, including schizophrenia and autism in which dysfunction has been implicated in the frontal lobes.