Cortical Mechanisms of Visual Category Recognition and Learning

拟议研究的总结和相关性 人类和其他高级动物有令人印象深刻的能力来识别行为的意义，或者 类别成员，范围广泛的感官刺激。这种能力，这是由一些大脑中断 疾病和病症如阿尔茨海默病、精神分裂症、中风和注意力缺陷障碍， 它之所以重要，是因为它使我们能够对我们所面临的持续不断的刺激和事件做出适当的反应。 在我们与环境的互动中。当然，我们并不是生来就有一个内置的图书馆， 有意义的类别，如“桌子”和“椅子”，我们被预先编程识别。而是 学会通过经验来认识这些刺激的意义。本文提出的研究目标是 更深入地了解学习和识别的大脑机制 视觉类别。最近的研究表明，后顶叶皮层和前额叶皮层都是 参与编码视觉刺激的类别成员资格和形成分类决策。在这些 在一项研究中，我们记录了顶叶皮层神经元在分类任务中的表现， 360º的运动方向被分为两个任意类别，这两个类别由学习类别划分 边界这些记录显示，这两个区域的神经元都根据它们的神经元编码刺激。 学习类别成员资格，表明顶叶视觉表征可以反映抽象信息 视觉刺激的学习意义拟议研究的目标是开发一种机制， 理解视觉皮层中的视觉特征表征如何快速转化为类别 顶叶和前额叶皮层的编码，以了解灵活的基于规则的决策机制 并确定神经元类别表征在类别过程中如何在真实的时间内发展 学习过程 虽然我们对大脑如何处理简单的感觉特征（如颜色、方向和视觉）有很多了解， 运动的方向），但对大脑如何学习和表示运动的意义或类别知之甚少。 刺激。更好地理解视觉学习和分类对于解决一些问题至关重要。 脑疾病和病症（例如中风、阿尔茨海默氏病、注意力缺陷障碍、精神分裂症，和 中风），使患者在需要视觉学习、识别和/或评估的日常任务中受损 并对感官信息做出适当的反应。这个项目的长期目标是指导下一个 通过帮助开发详细的治疗方法， 理解学习、记忆和识别的大脑机制。这些研究还 与理解和解决学习障碍有关，如注意力缺陷障碍， 阅读障碍，这影响了相当一部分学龄儿童和年轻人。因此，更详细的 了解学习和注意力的基本大脑机制可能会给我们提供重要的 深入了解涉及这些认知能力的疾病的原因和潜在的治疗方法。

Summary and Relevance of Proposed Research Humans and other advanced animals have an impressive capacity to recognize the behavioral significance, or category membership, of a wide range of sensory stimuli. This ability, which is disrupted by a number of brain diseases and conditions such as Alzheimer's disease, schizophrenia, stroke, and attention deficit disorder, is critical because it allows us to respond appropriately to the continuous stream of stimuli and events that we encounter in our interactions with the environment. Of course, we are not born with a built in library of meaningful categories, such as “tables” and “chairs”, which we are preprogrammed to recognize. Instead, we learn to recognize the meaning of such stimuli through experience. The goal of the studies proposed here is to move towards a more detailed understanding of the brain mechanisms underlying the learning and recognition visual categories. Recent work has shown that both the posterior parietal cortex and prefrontal cortex are involved in encoding the category membership of visual stimuli and forming categorical decisions. In these studies, we recorded from neurons in the parietal cortex during performance of a categorization task in which 360º of motion directions were grouped into two arbitrary categories that were divided by a learned category boundary. These recordings revealed that neurons in both areas robustly encoded stimuli according to their learned category membership, suggesting that parietal visual representations can reflect abstract information about the learned significance of visual stimuli. The goals of the proposed studies are to develop a mechanistic understanding of how visual feature representations in visual cortex are rapidly transformed into category encoding in parietal and prefrontal cortices, to understand the mechanisms of flexible rule-based decision making, and to determine how neuronal category representations develop in real time during the category learning process. While much is known about how the brain processes simple sensory 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 learning and 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 more detailed understanding of the basic brain mechanisms underlying learning and attention will likely give important insights into the causes and potential treatments for disorders involving these cognitive faculties.