Micro- and macro-scale cortical dynamics underlying visual attention

描述（由申请人提供）：视觉世界包含的信息比大脑所能处理的要多。幸运的是，我们有能力通过选择性注意机制来影响哪些信息源得到优先处理，这种能力对日常生活至关重要。注意力涉及整个大脑在全球水平上的协调，以控制在局部水平上运作的功能专业化大脑区域处理资源的平衡。然而，迄今为止，用于研究注意力神经基础的实验室技术，如人类头皮脑电图和灵长类动物的单单元记录，一次只能对这两种操作水平中的一种敏感。本研究项目的目标是将这两种方法结合在一个单一的综合调查中，以表征这两个水平的大脑功能，整体和局部，如何在控制选择性注意过程中相互作用。我们已经制定了一个精心调整的研究策略，将通过三个系统和具体的目标来实现这一总体目标。我们将首先建立在小群神经元的相关变异性和在头皮上测量的脑电图信号之间的联系的基线测量，无论是在自发的大脑状态还是在基本的视觉感知期间。然后，我们将通过引入内生选择性注意任务来增加复杂性，使我们能够将我们的范围从低级感知扩展到更高层次的认知过程。最后，考虑到从前两个目标中获得的知识的潜在应用，我们将使用“闭环”系统监测注意力信号。这将使我们能够监测动物的自然注意力波动，以便以情境最佳的方式呈现刺激。这种“大脑状态随机”系统将在广泛的应用中具有明显的优势。由于这是一个培训奖项，该项目的另一个主要目标是培训Adam C. Snyder博士，一位有前途的博士后，在非人类灵长类动物的单单元电生理学所需的技术方面，以及在他作为独立科学家的漫长而富有成效的职业生涯中所需要的专业实践。在该项目结束时，Snyder博士将接受灵长类动物电生理学实践方面的一流培训，这将补充他在人类脑电图方法方面的成熟和成熟的专业知识，加强他作为创新和成功的神经科学家的基础。从科学的角度来看，我们将开发出一种跨越局部和全局大脑功能水平的注意力控制模型。这一进展不仅有利于注意力研究本身，而且将为未来研究其他在空间尺度上类似运作的大脑过程提供一个框架。了解健康个体的注意功能对于指导对包括自闭症、精神分裂症和注意缺陷障碍在内的涉及注意缺陷的疾病的潜在治疗干预至关重要。

DESCRIPTION (provided by applicant): The visual world contains more information than the brain can process. Fortunately, we have some ability to influence which sources of information receive processing priority through the mechanism of selective attention, and this ability is critical for daily life. Attention involves coordination across the brain at a global level to contol the balance of processing resources in functionally-specialized brain areas operating at a local level. To date, however, laboratory techniques for investigating the neural bases of attention, such as human scalp EEG and single-unit recordings in primates, have been sensitive to only one of these two levels of operation at a time. The goal of this research project is to combine these two methods in a single comprehensive investigation to characterize how these two levels of brain function, the global and the local, interact during control of selective attention. We hav developed a carefully titrated research strategy that will achieve this overarching goal through three systematic and specific aims. We will begin by establishing baseline measures of the links between correlated variability in small populations of neurons and EEG signals measured at the scalp, both in the spontaneous brain state as well as during basic visual perception. We will then add a layer of complexity by introducing an endogenous selective attention task, enabling us to expand our scope beyond low-level perception to higher-level cognitive processes. Finally, with an eye for potential applications of the knowledge gained from the preceding two aims, we will monitor attention signals with a 'closed-loop' system. This will enable us to monitor the animals' natural attentional fluctuations in order to present stimuli in a contextually optimal fashion. Such a 'brain-state-contingent' system would have clear advantages across a wide range of applications. Since this is a training award, another major goal of this project is the training of Dr. Adam C. Snyder, a promising postdoctoral fellow, in the techniques required for single-unit electrophysiology in non-human primates, as well as the professional practices that will be needed throughout what will undoubtedly be his long and productive career as an independent scientist. At the end of this project, Dr. Snyder will have received first-rate trainin in the practices of primate electrophysiology, which will complement his established and proven expertise in human EEG methods, strengthening his foundation as an innovative and successful neuroscientist. From a scientific perspective, we will have developed a model of attention control that spans local and global levels of brain function. This advancement will not only benefit attention research itself, but will provide a framework for future investigations of other brain processes that similarly operate across a range of spatial scales. An understanding of the functioning of attention in health individuals is essential to guide potential therapeutic interventions in disorders involving deficits in attention, including autism, schizophrenia and attention deficit disorder.