Attentional Functions of the Pulvinar

描述（由申请人提供）：从杂乱的环境中选择相关信息进行进一步处理是指导行为的最基本的认知能力之一。当注意力选择机制失效时，这一点变得非常明显，比如在患有多动症、中风后经常观察到的视觉空间半忽视和精神分裂症的个体中。来自生理学和脑功能成像研究的证据表明，注意选择发生在视觉通路的多个阶段。例如，早在外侧膝状核和每个连续的视觉处理阶段，神经反应就受到对目标位置的空间定向注意的调节。这些调节影响似乎是由额叶和顶叶皮层的高阶区域网络产生的，包括额叶视野和外侧顶叶内区（LIP）。虽然在皮层水平上对注意机制的理解已经做出了很多努力，但皮层下区域的功能作用却没有得到很好的定义。人类和猕猴病变研究的证据表明，一个大的丘脑核，即枕核，在选择过程中起着重要作用。枕核与额顶叶皮层和视觉皮层广泛相连，因此能够很好地影响皮层之间的交流。然而，很少有生理学研究在注意选择任务中探测枕核活动。本研究的目标是描述枕核的注意功能（SA #1），以及在注意选择过程中枕核和皮层如何相互作用（SA #2）。中心假设是枕状核协调皮层区域的活动，以便根据注意力要求调节信息传递。为了验证这一假设，我们将在猴子执行选择性注意任务时同时记录枕核和皮质区LIP的神经活动。本研究旨在促进我们对灵长类动物大脑中调节注意力功能的神经机制和网络相互作用的理解。了解选择性注意的基本机制是开发有效的注意力缺陷治疗策略的第一步。

DESCRIPTION (provided by applicant): The selection of relevant information from cluttered environments for further processing is one of the most fundamental cognitive abilities for guiding behavior. This becomes strikingly clear when attentional selection mechanisms fail, such as in individuals afflicted with ADHD, visuospatial hemineglect that is often observed after stroke, and schizophrenia. Converging evidence from physiology and functional brain imaging studies reveals that attentional selection occurs at multiple stages along the visual pathway. E.g. neural responses are modulated by spatially directed attention to a target location as early as in the lateral geniculate nucleus and at each successive visual processing stage. These modulatory influences appear to be generated by a network of higher-order areas in frontal and parietal cortex including the frontal eye fields and lateral intraparietal area (LIP). While much effort has been made towards an understanding of attentional mechanisms at the cortical level, the functional role of subcortical areas is poorly defined. There is evidence from human and macaque lesion studies that a large thalamic nucleus, the pulvinar, plays an important role in the selection process. The pulvinar is widely connected with fronto-parietal and visual cortex and is thus well positioned to influence communication across the cortex. However, very few physiology studies probing pulvinar activity during attentional selection tasks have been performed. The goal of the proposed research is to characterize attentional function in the pulvinar (SA #1) and to characterize how the pulvinar and cortex interact during attentional selection (SA #2). The central hypothesis is that the pulvinar coordinates activity in cortical areas, in order to regulate information transmission according to attentional requirements. To test this hypothesis, we will simultaneously record neural activity in the pulvinar and cortical area LIP, while monkeys perform a selective attention task. The proposed research is aimed at advancing our understanding of the neural mechanisms and the network interactions that mediate attentional functions in the primate brain. Progress in understanding the basic mechanisms of selective attention is a first necessary step in developing effective treatment strategies for attentional deficits. PUBLIC HEALTH RELEVANCE: This research is relevant to public health because it is expected to advance our understanding of neural mechanisms underlying selective attention, which is one of the most fundamental cognitive abilities for guiding behavior. This becomes strikingly clear when attentional selection mechanisms fail, such as in individuals afflicted with ADHD, visuo-spatial hemineglect that is often observed following stroke, and schizophrenia. Progress in understanding the basic mechanisms of selective attention is a first necessary step in developing effective treatment strategies for attentional deficits.