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、有效地交流和在我们复杂的世界中导航至关重要。虽然目前还不清楚这两种模式的信息在大脑中的哪里被结合和处理，以管理特定的行为，但额叶已经被确定为与记忆和语言相关的区域，这依赖于跨感觉整合。此外，最近对猕猴前额叶皮质下凸性(IFC)的分析揭示了视觉和听觉加工的并列和重叠区域，表明可能在多模式感觉整合中发挥作用。以前对前额叶皮质的研究主要集中在它在视觉记忆处理中的作用。这个项目的目标是对额叶如何处理复杂的听觉、视觉和组合刺激有一个基本的了解，这些刺激服务于有意义的交流和物体识别。我们的实验将集中在猕猴IFC的神经生理学和解剖学分析上。具体地说，实验将表征IFC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式的(即对视觉和听觉刺激的组合反应)。此外，我们还将比较被动呈现或联想记忆任务中呈现的多模式刺激对单位反应的调制。最后，我们将通过确定IFC生理特征区域的解剖联系来阐明额叶听觉、视觉和多模式反应背后的神经回路。这项研究的发现将有助于揭示与言语感知相关的沟通过程背后的电路和细胞机制。我们的发现也将对理解影响沟通和语言的神经障碍，包括精神分裂症和自闭症，额叶功能障碍有影响。

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.