Comparison of Frontal Cortex and Striatum during Visual Categorization

描述（由申请人提供）：正常的认知依赖于前额皮质（RFC）和基底神经节（BG）之间的相互作用。在包括精神分裂症、帕金森氏病、亨廷顿氏病和多动症在内的许多神经精神疾病中观察到的认知障碍与它们的功能障碍有关。因此，了解PFC和BG之间各自的贡献和合作对于开辟治疗这些疾病的途径至关重要。然而，我们对这些区域的正常功能知之甚少，因为它们的神经活动在很大程度上是单独研究的，由不同的实验室在不同的猴子中执行不同的任务。这一提议的目的是通过在猴子执行认知要求高的任务时，同时在每个区域植入多个电极，通过记录来推进我们的理解，这将测试假设，即基底神经节负责简单关联的获取和实现，而PFC将这些信息碎片到整个任务结构的更高层次表示中。这个项目将通过扩展对一种新型目标导向行为的调查来检验这一假设。之前的研究采用了带有强烈运动成分的规则；相反，我将使用分类学习。它是认知的基础，可以与运动反应分离。猴子的神经生理学研究和人类的功能磁共振成像研究表明PFC和BG都参与了分类，但它们从未被直接比较过。本提案的目的1是直接比较PFC和BG的视觉类别信息。这将使我们能够比较神经类别信息的普遍性、强度和潜伏期，并检查大脑区域内部和大脑区域之间的精确时间关系，从而深入了解它们各自的作用以及信息如何在它们之间传递。先前的研究还表明，熟悉的、高阶的、运动相关的规则在运动前皮层（PMC）中比在PMC中有更强的表征，并且潜伏期更短。因此，PMC可能具有巩固与经常使用的任务有关的信息的功能。但我们不知道这是否仅限于有运动成分的规则；非运动规则，如视觉分类，从未在PMC中被检查过。这就是第二个目标的目标，直接比较运动前皮层、前额叶皮层和BG中的视觉类别信息。通过直接比较这三种结构的神经活动，我希望能够深入了解它们在基本认知功能-分类中的作用。通过了解这些大脑区域的正常功能及其各自在认知中的作用，我们可以更好地了解如何治疗涉及这些区域的患者的疾病。

DESCRIPTION (provided by applicant): Normal cognition depends on interactions between the prefrontal cortex (RFC) and basal ganglia (BG). The cognitive impairments observed in a host of neuropsychiatric disorders including schizophrenia, Parkinson's disease, Huntington's disease, and ADHD have been linked to their dysfunction. Thus, understanding the respective contributions and collaborations between the PFC and BG will be critical to opening paths to treatment of these disorders. However, we understand little about the normal functioning of these areas because their neural activity has largely been studied separately, by different laboratories in different monkeys performing different tasks. The aim of this proposal is to advance our understanding by recording from multiple electrodes simultaneously implanted in each region while monkeys perform a cognitively demanding task that will test the hypothesis that the basal ganglia is responsible for the acquisition and implementation of simple associations while the PFC pieces such information into a higher-level representation of the entire task structure. This project will test this hypothesis by extending investigations to a novel type of goal-directed behavior. Previous studies have employed rules with a strong motor component; in contrast, I will use categorical learning. It is fundamental to cognition and can be dissociated from motor responses. Neurophysiological studies in monkeys and fMRI studies in humans indicate involvement of both the PFC and BG in categorization, but they have never been directly compared. Aim 1 of this proposal is to directly compare visual category information in PFC versus BG. This will allow us to compare the prevalence, strength, and latency of neural category information and to examine precise timing relationships within and between brain areas that can provide insight into their respective roles and how information is transferred between them. Prior studies also indicate that familiar, higher-order, motor-related rules are even more strongly represented and have a shorter latency in the premotor cortex (PMC) than the PFC. Thus, the PMC may function to consolidate information pertaining to frequently utilized tasks. But we do not know if this is only limited to rules with a motor component; non-motor rules such as visual categories have never been examined in the PMC. This is the goal of the second aim, to directly compare visual category information in premotor cortex, prefrontal cortex, and the BG. By directly comparing neural activity in these three structures, I hope to provide insight into their roles in a fundamental cognitive function - categorization. By understanding the normal functioning of these brain regions and their respective roles in cognition, we may better understand how to approach treatments for patients whose afflictions involve them.