Interaction of Visual and Oculomotor Signals in Cortex

描述(申请人提供)：近年来，来自心理物理、神经成像和神经生理学研究的证据表明，基本的视觉感知和认知功能，如注意力和工作记忆，出现在皮质中眼动信号和视觉表征的相互作用中。我们以前的工作表明，涉及额叶眼场的眼跳相关信号有助于视觉刺激的注意选择和大脑皮质中与注意相关的视觉信号的过滤。在目前的建议中，我们计划进一步研究与眼跳相关的信号对视觉表征的影响，包括三个互补的目标。在第一个目标中，我们将解决我们先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是必要的和充分的。我们将测试FEF神经元的作用，并将其直接与区域嘴唇神经元进行比较，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，以及研究其对另一个区域(LIP或FEF)神经元的注意行为和注意调节的影响来实现。在第二个目标中，我们将使用自愿产生的眼跳来探索眼跳目标选择与视觉皮层中注意的神经关联之间的关系。具体地说，我们将研究眼跳准备对V4区自下而上和基于特征的注意的神经关联的影响。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持中所起的作用。具体地说，我们将测试FEF微刺激对下颞叶皮质视觉工作记忆及其相关因素的影响，并同时记录工作记忆过程中两个区域神经元的记录。这三个目标将使我们能够确定眼跳相关信号在多大程度上影响大脑皮层视觉表征的选择和保持，以及这些影响与视觉感知、认知和视觉引导行为的相关性。这项研究提出的问题对于理解视觉引导行为的神经基础至关重要，因此，实现这些目标将对视觉运动整合、知觉和认知障碍的神经基础和治疗具有直接和重要的影响。这类障碍的关键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眼球运动控制缺陷。这项拟议的研究与ADHD特别相关，ADHD在美国困扰着超过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，了解视觉注意的神经基础显然对人类健康具有重要意义。 公共卫生相关性：拟议研究的目标对于理解视觉引导行为的神经基础至关重要，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影响。这类障碍的关键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眼球运动控制缺陷。这项拟议的研究与ADHD特别相关，ADHD在美国困扰着超过5%的儿童，使其成为影响儿童的最常见的精神障碍之一。

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.