Interaction of Visual and Oculomotor Signals in Cortex

描述（申请人提供）：近年来，心理物理学、神经影像学和神经生理学研究的证据表明，基本的视觉知觉和认知功能，如注意力和工作记忆，是由眼动信号和皮层视觉表征的相互作用产生的。我们之前的研究表明，涉及额叶视野（FEF）的眼跳相关信号有助于视觉刺激的注意选择和皮层中视觉信号的注意相关过滤。在本提案中，我们计划在三个互补的目标中进一步研究眼跳相关信号对视觉表征的影响。在第一个目标中，我们将讨论我们之前研究的一个重要含义，即FEF神经元的活动对于驱动空间注意力是必要和充分的。我们将测试FEF神经元的作用，并将其直接与区域LIP神经元进行比较，后者也被认为对注意力至关重要。这将通过药物诱导两个区域之一（FEF或LIP）的神经元激活和失活，并研究其对另一个区域（LIP或FEF）神经元的注意表现和注意调节的影响来实现。在第二个目标中，我们将使用自愿生成的扫视来追求扫视目标选择与视觉皮层中注意神经相关的关系。具体而言，我们将研究扫视准备对V4区域自下而上和基于特征的注意神经相关的影响。在第三个目标中，我们将研究FEF在工作记忆中视觉信息的选择和保留中的作用。具体来说，我们将测试FEF微刺激对视觉工作记忆及其相关的下颞叶皮层的影响，并同时记录工作记忆表现时这两个区域的神经元。总之，这三个目标将使我们能够确定与眼跳相关的信号在多大程度上影响皮层中视觉表征的选择和保留，以及这些影响与视觉感知认知和视觉引导行为的相关性。所提出的研究解决的问题是理解视觉引导行为的神经基础的核心，因此实现这些目标将对视觉运动整合，感知和认知障碍的神经基础和治疗具有直接和重要的意义。这类疾病的主要例子包括注意力缺陷多动障碍（ADHD）和阅读障碍，这两种疾病似乎都包括动眼肌控制缺陷。这项提议的研究与多动症特别相关，多动症折磨着美国超过5%的儿童，使其成为影响儿童的最常见的精神障碍之一。因此，理解视觉注意的神经基础显然对人类健康具有重要意义。

DESCRIPTION (provided by applicant): In recent years, evidence from psychophysical, neuroimaging and neurophysiological studies has accumulated suggesting that basic visual perceptual and cognitive functions such as attention and working memory emerge from the reciprocal interaction of oculomotor signals and visual representations in cortex. Our previous work suggests that saccade-related signals involving the frontal eye field (FEF) contribute to the attentional selection of visual stimuli and to the attention-related filtering of visual signals in cortex. In the present proposal, we plan to further examine the influence of saccade-related signals on visual representations in a set of three complimentary aims. In the first aim, we will address an important implication of our previous studies, namely that the activity of FEF neurons is necessary and sufficient for driving spatial attention. We will test the role of FEF neurons and compare it directly to that of area LIP neurons, which are also believed to be critical for attention. This will be accomplished via pharmacologically induced activation and inactivation of neurons in one of the two areas (FEF or LIP) and a study of its effects on attentional performance and the attentional modulation of neurons in the other area (LIP or FEF). In the second aim, we will use voluntarily generated saccades to pursue the relationship between saccade target selection and neural correlates of attention in visual cortex. Specifically, we will study the influence of saccade preparation on neural correlates of bottom-up and feature-based attention in area V4. In the third aim, we will examine the role of the FEF in the selection and retention of visual information in working memory. Specifically, we will test the effects of FEF microstimulation on visual working memory and its correlates in inferior temporal (IT) cortex as well as record simultaneously from neurons in both areas during working memory performance. Together, these three aims will allow us to determine the extent to which saccade-related signals influence the selection and retention of visual representations in cortex and the relevance of those influences to visual perception cognition, and visually guided behavior. The questions addressed by the proposed research are central to an understanding of the neural basis of visually guided behavior, and thus achieving those goals will have direct and important implications for the neural bases and the treatment of disorders of visuomotor integration, perception and cognition. Key examples of such disorders include attention-deficit hyperactivity disorder (ADHD) and dyslexia, both of which appear to include deficits in oculomotor control. The proposed research is particularly relevant to ADHD, which afflicts more than five percent of children in the U.S., making it one of the most common mental disorders to affect children. Thus an understanding of the neural basis of visual attention clearly has important implications for human health. PUBLIC HEALTH RELEVANCE: The goals of the proposed research are central to an understanding of the neural basis of visually guided behavior, and thus achieving those goals will have direct and important implications for the neural bases and the treatment of disorders of visuomotor integration, perception and cognition. Key examples of such disorders include attention-deficit hyperactivity disorder (ADHD) and dyslexia, both of which appear to include deficits in oculomotor control. The proposed research is particularly relevant to ADHD, which afflicts more than five percent of children in the U.S., making it one of the most common mental disorders to affect children.