Probing perception and attention using primate optogenetics

描述（由申请人提供）：在拟议的研究中，我们将使用一种新开发的灵长类动物光遗传学工具，这使我们能够在清醒的行为猴子的新皮层内创建可逆的“微损伤”。使用这个工具，我们将测试和量化猕猴V4区的作用，这是腹侧视觉处理流中处理的中间阶段。在目标1中，我们将研究这种新工具如何调节神经元反应的增益，并将量化激活区域作为照明水平的函数。V4区有一个不规则的组织，一些区域对颜色有选择性，另一些区域对方向有选择性。在目标2中，我们将测试V4在颜色和方向感知中的作用，让猴子对颜色和方向进行精细的辨别，而我们则对颜色或方向选择性神经元进行标记。我们将研究激活颜色神经元是否会损害颜色判断，而不是方向判断，以及激活方向神经元是否会损害方向判断，而不是颜色判断。我们还将研究，当我们调整神经元的判别式，或者，调整，使调谐曲线的陡峭部分适合判别判别之间，这种损害是否更大。在目标3中，我们将使用光遗传学微损伤来测试V4是否在介导注意力选择中起因果作用。我们收集的数据将提供最直接的证据支持或反对V4在颜色和方向感知中起因果作用的命题，以及它是否在注意力选择中起因果作用。此外，拟议的研究将展示这种新的光遗传学工具的使用，我们将公开提供，以便其他研究灵长类动物和其他物种的研究人员可以使用这种工具来测试感知，认知和行动的理论。

DESCRIPTION (provided by applicant): In the proposed research, we will use a newly developed primate optogenetic tool, which enables us to create reversible "micro lesions" within the neocortex of awake, behaving monkeys. Using this tool, we will test and quantify the role of macaque Area V4, an intermediate stage of processing within the ventral visual processing stream. In Aim 1, we will examine how this new tool modulates the gain of neuronal responses, and will quantify the region of activation as a function of illumination level. Area V4 has a patchy organization, with some regions being selective for color, and others selective for orientation. In Aim 2, we will test the role of V4 in the perception of color and of orientation, by having monkeys make fine discriminations of color and orientation, while we inactivate patches color- or orientation-selective neurons. We will examine whether activating the neurons tuned for color impairs color judgments, and not orientation judgments, and whether activating the neurons tuned for orientation impairs orientation judgments, and not color judgments. We will also examine whether this impairment is greater when we inactivate neurons tuned for the discriminanda or, alternatively, tuned such that the steep part of the tuning curve is suited to discriminate among discriminanda. In Aim 3, we will use optogenetic micro lesions to test whether V4 plays a causal role in mediating attentional selection. The data we collect will provide the most direct evidence for or against the proposition that V4 plays a causal role in the perception of color and of orientation, and whether it plays a causal role in attentional selection. In addition, the proposed research will demonstrate the use of this new optogenetic tool, and we will make it publicly available, so that other researchers working in primates and in other species, can use this tool to test theories of perception, cognition and action.