Cortical Mechanisms of Visual Category Recognition and Learning

拟议研究的摘要和相关性 人类有一种令人印象深刻的能力来识别感官刺激的类别成员。这种能力， 它被一种基于大脑的疾病和状况所干扰，如阿尔茨海默氏症，精神分裂症， 中风和注意力缺陷障碍是至关重要的，因为它允许我们对刺激和 我们在环境中遇到的事件。我们并不是与生俱来就有一个类别库的 预编程序可以识别。相反，我们通过体验了解熟悉的类别。我们的工作 研究表明，大脑后顶叶皮质(PPC)和前额叶皮质(PFC)参与了大脑皮层的分类 决定。在视觉运动分类任务中，我们记录了PPC和PFC的神经元，揭示了 这两个区域的神经元根据它们学习到的类别成员对刺激进行强有力的编码。这说明， 这两个区域都参与了抽象视觉范畴信息的表征。我们还展示了这一活动 In PPC与范畴决定有因果关系，使用可逆的失活。这个项目用的是小说 监测额眼顶内外侧区大型神经元群活动的记录技术 领域，和上丘，在绝对的决定。这将产生一种机械地理解如何 这三个区域之间的相互作用使得作为分类决策基础的计算成为可能。这部作品 也将决定包括眼睛在内的多种行为功能是如何由这个大脑网络来调节的 运动和注意力，以及评估每个大脑区域对分类决策的因果意义。 虽然对大脑如何处理视觉特征(如颜色、方向和方向)已知很多 运动)，人们对大脑如何学习和表示刺激的意义或类别知之甚少。一个 更好地理解视觉分类对于解决许多脑部疾病和 疾病(如中风、阿尔茨海默病、注意力缺陷障碍、精神分裂症和中风) 在需要视觉学习、识别和/或评估和反应的日常任务中受损的患者 恰如其分地传递感官信息。该项目的长期目标是指导下一代 通过帮助发展对这些基于大脑的疾病和障碍的详细了解 作为学习、记忆和识别基础的大脑机制。这些研究也与 理解和解决学习障碍，如注意力缺陷障碍和阅读障碍，这会影响 相当一部分学龄儿童和年轻人。由此，详细了解了基本的 绝对决策和注意力的大脑机制可能会对原因和 涉及这些认知和知觉能力的疾病的潜在治疗方法。

Summary and Relevance of Proposed Research Humans have an impressive capacity to recognize the category membership of sensory stimuli. This ability, which is disrupted by a brain-based diseases and conditions such as Alzheimer’s disease, schizophrenia, stroke, and attention deficit disorder, is critical because it allows us to respond appropriately to stimuli and events that we encounter in the environment. We are not born with an innate library of categories which we are preprogrammed to recognize. Instead, we learn about familiar categories through experience. Our work showed that the posterior parietal cortex (PPC) and prefrontal cortex (PFC) are involved in categorical decisions. We recorded from neurons in PPC and PFC during visual motion categorization tasks, revealing that neurons in both areas robustly encode stimuli according to their learned category membership. This shows that both regions are involved in representing abstract visual categorical information. We also showed that activity in PPC is causally related to categorical decisions, using reversible inactivation. This project uses novel recording techniques to monitor activity of large neural populations in the lateral intraparietal area, frontal eye field, and superior colliculus during categorical decisions. This will yield a mechanistic understanding of how interactions between these three regions enable computations which underlie categorical decisions. This work will also determine how multiple behavioral functions are mediated by this brain network, including eye movements and attention, as well assess the causal significance of each brain area to categorical decisions. While much is known about how the brain processes visual features (such as color, orientation, and direction of motion), less is known about how the brain learns and represents the meaning, or category, of stimuli. A greater understanding of visual categorization is critical for addressing a number of brain diseases and conditions (e.g. stroke, Alzheimer’s disease, attention deficit disorder, schizophrenia, and stroke) that leave patients impaired in everyday tasks that require visual learning, recognition and/or evaluating and responding appropriately to sensory information. The long-term goal of this project is to guide the next generation of treatments for these brain-based diseases and disorders by helping to develop a detailed understanding of the brain mechanisms that underlie learning, memory and recognition. These studies also have relevance for understanding and addressing learning disabilities, such as attention deficit disorder and dyslexia, which affect a substantial fraction of school age children and young adults. Thus, a detailed understanding of the basic brain mechanisms of categorical decisions and attention will likely give important insights into the causes and potential treatments for disorders involving these cognitive and perceptual abilities.