Dissociating feature- and space-based attention in the frontoparietal network

描述(由申请者提供)：注意力是视觉感知的重要组成部分，它允许大脑根据当前的任务需求分配有限的资源。大多数研究都集中在我们隐蔽地注意到视野中特定区域的能力(空间注意)，但我们也可以关注特定的视觉特征，而不是空间位置(基于特征的注意)。对空间注意的研究已经确定了额叶和顶叶皮质的高阶区域网络，它们似乎是这些调制信号的来源。最近的研究表明，与空间注意有关的额顶网络可能在注意加工中发挥更普遍的作用。然而，由于功能磁共振成像(FMRI)的方法学限制以及缺乏对猕猴的单细胞研究，该网络在基于特征的注意中的作用仍不清楚。综合运用行为学、神经成像和电生理学方法，本研究将探讨以下具体目标，以更清楚地界定额叶和顶叶区域在控制基于特征的注意中的作用。目的1：使用功能性磁共振成像适应范式，确定人类额叶和顶叶皮质对基于特征和空间的注意有贡献的区域。目的2：使用几乎相同的实验设计和方法，确定灵长类动物大脑中与人类区域具有相似反应特性的区域。目的3：利用fMRI引导的单单位记录，表征灵长类动物基于特征注意的区域，特别是与空间注意重叠的区域的神经元反应特性。这些实验将弥合间接测量人类神经活动(FMRI)和猴子单细胞研究之间的差距，并促进我们对有助于自上而下注意控制的神经机制和网络结构的理解。从自然环境中选择相关信息是指导行为的最基本的认知能力之一。视觉注意力在健康的大脑功能中起着重要的作用，在各种各样的大脑疾病中都会受到干扰，例如多动症、精神分裂症和中风后的空间偏执。对人脑正常注意功能的机制进行更全面的描述，将为评估和缓解这些功能障碍提供一个平台。

DESCRIPTION (provided by applicant): Attention is a critical component of visual perception that allows the brain to allocate its limited resources depending on current task demands. Most research has focused on our ability to covertly attend to a specific region within the visual field (spatial attention), but we can also attend to a specific visual feature, independent of spatial position (feature-based attention). Studies of spatial attention have identified a network of higher-order areas in frontal and parietal cortex that appear to be the source of these modulating signals. Recent studies suggest that the frontoparietal network implicated in spatial attention may play a more general role in attentional processing. However, the role of this network in feature-based attention remains unclear due to methodological limitations of functional magnetic resonance imaging (fMRI) and the lack of single cell studies in the macaque. Using a combined behavioral, neuroimaging, and electrophysiological approach, this proposal will address the following specific aims to more clearly define the role of frontal and parietal regions in the control of feature-based attention. Aim 1: Identify regions of human frontal and parietal cortex that contribute to feature- and space-based attention using an fMRI-adaptation paradigm. Aim 2: Identify regions of the primate brain that have similar response properties compared to the human regions using virtually the same experimental design and methods. Aim 3: Characterize the neuronal response properties in regions involved in feature-based attention, particularly those that overlap with spatial attention, in primates using fMRI-guided single-unit recordings. These experiments will bridge the gap between indirect measure of neural activity in humans (fMRI) and single cell studies in monkeys and advance our understanding of the neural mechanisms and the network architecture contributing to top-down attentional control. The selection of relevant information from the natural environment is one of the most fundamental cognitive abilities for guiding behavior. Visual attention plays a prominent role in healthy brain functioning and is disrupted in a wide variety of brain disorders, such as ADHD, schizophrenia and spatial hemineglect following stroke. A more complete characterization of the mechanisms subserving normal attentional functions in the human brain will provide a platform from which to evaluate and alleviate these dysfunctions.