CORTICAL CIRCUIT BASIS OF VISUAL SPATIAL PROCESSING

描述（由申请人提供）：阐明感知和认知的生物学基础一直是神经科学研究的一个持久目标，因为它对于治疗可能破坏思考和行动能力的大脑疾病至关重要。传统上认为，高级的心理过程是由前额皮质负责的，前额皮质是高级灵长类动物和人类大脑中最发达的部分。然而，近年来，人们已经清楚地认识到，许多与心理功能相关的神经并不是前额皮质独有的特征，而是在投射到前额皮质的皮质通路中已经很明显，例如，颞叶和顶叶的关联区。因此，揭示这些皮质区域的独特和合作作用对于理解高级心理功能的生物学基础是必要的。关于高阶皮层区域之间神经处理的回路组织和性质如何不同，从而解释它们不同的功能角色，我们所知的就更少了。我们建议使用一个综合的方法框架来阐明与视觉空间信息处理有关的区域的独特和合作作用。我们将比较研究背侧前额叶和后顶叶皮层的生理反应和神经回路组织。我们的实验将利用神经生理学记录，在训练猴子执行视觉空间任务时，用间隔紧密的电极阵列进行记录。我们将研究多个视觉刺激同时或依次呈现时的神经反应模式，并分析神经元之间的功能相互作用。实验将专门测试前额皮质是否具有更强大，更广泛分布或动态调节的神经元连接，或功能特化的细胞类型。这些实验将有助于揭示涉及高级认知功能的皮质区域的功能专门化，并为正常的感知处理以及脑损伤和精神疾病的后果提供见解。了解调节高级认知过程的皮质区域的组织和功能是改善可能破坏人的思考和行动能力的疾病的关键。这项拟议的研究将依赖于灵长类动物模型来确定大脑皮层中参与视觉空间信息处理的两个区域的作用和功能分工，即后顶叶皮层和背前额叶皮层。

Description (provided by applicant): Elucidating the biological basis of perception and cognition has been an enduring goal of neuroscience research because it is essential for treating brain disorders that can devastate the ability to think and act. Higher mental processes have traditionally been attributed to the prefrontal cortex, the part of the brain most developed in higher primates and humans. In recent years, however, it has become clear that many neural correlates of mental functions are not exclusive traits of the prefrontal cortex but are already evident in the cortical pathways that project to it, for example, the association areas of the temporal and parietal lobes. Uncovering the unique and cooperative roles of these cortical regions is therefore necessary for understanding the biological basis of higher mental functions. Even less is known about how the circuit organization and nature of neural processing differs between high-order cortical areas, so as to account for their distinct functional roles. We propose to use an integrative methodological framework to elucidate the unique and cooperative roles of areas involved with the processing of visual-spatial information. We will comparatively investigate the physiological responses and neural-circuit organization of the dorsal prefrontal and posterior parietal cortex. Our experiments will make use of neurophysiological recordings with arrays of closely-spaced electrodes in monkeys trained to perform visual-spatial tasks. We will examine the patterns of neural responses during the presentation of multiple visual stimuli, concurrently or in sequence, and analyze the functional interactions between neurons. Experiments will specifically test whether prefrontal cortex is characterized by more robust, more widely distributed or dynamically modulated neuronal connectivity, or functionally specialized cell types. These experiments will help unveil the functional specialization of cortical areas involved in higher cognitive functions and offer insights on normal perceptual processing as well as the consequences of brain injury and mental illness. PUBLIC HEALTH RELEVANCE Understanding the organization and function of cortical areas mediating higher cognitive processes is key to ameliorating the disorders that can devastate one's ability to think and act. The proposed research will rely on a primate model to determine the role and functional specialization of two areas of the cerebral cortex involved in the processing of visual spatial information, the posterior parietal and dorsal prefrontal cortex.