Causal testing of the role of a place code for global-scale visual features in primate V1 using patterned optogenetics

人类对物体的整体形状高度敏感，这是物体识别的关键步骤。一个假设 大脑利用视觉皮层表面的刺激诱发活动的传播形状， 为了处理形状，利用视网膜-神经元的良好记录的组织作为投影的 大脑皮层表面的视野我们小组先前的工作发现， 大脑皮层保存着可以用来解码刺激的整体形状的信息，但是大脑是否 实际上使用这些信息是迄今为止未知的。目前的建议旨在测试假设， 大脑皮层活动的形状可以通过观察对形状的感知是否可以 是通过人为地唤起视觉皮层的形状活动而产生的。 我将使用光遗传学唤起这种形状的神经元活动，这是一种人工刺激神经元的技术， 光通过控制激发光的模式，我可以控制我唤起的活动的形状。如果我能用这个 光遗传学刺激以使执行形状辨别任务的猕猴偏向于报告看到 形状对应于人工插入的活动，这将表明大脑依赖于视网膜定位。 大脑皮层对视觉中的形状进行处理的活动。 目标1中的实验将描述猕猴执行简化形状辨别任务的行为 以及在执行任务时记录的神经元信号，以及详细的电位计算模型， 神经元策略目标2的重点是开发精确成型所需的管道 光遗传学诱发的活动。目标3将是一个实验，其中光遗传学将用于引入 一个特定形状的人工活动进入猕猴的视觉皮层执行形状辨别任务。 我将看到行为，从而可能的感知，是否会受到人工神经元添加的系统性影响。 仅通过其在皮层上传播的形状来包含信息的活动。拟议工作 将是一个重要的贡献，我们如何理解形状是在视觉处理，并将有广泛的 模式化光遗传学刺激在翻译环境中的效用的含义， 神经修复术来恢复视力

Humans are highly sensitive to the overall shape of objects—a critical step in object identification. One hypothesis is that the brain uses the shape of the spread of stimulus-evoked activity across the surface of visual cortex in order to process shape, exploiting retinotopy—the well-documented organization of neurons as a projection of the visual field across the surface of the cortex. Prior work from our group has found that the shape of activity across the cortex holds information that can be used to decode the overall shape of a stimulus, but whether the brain actually uses this information is as of yet unknown. The current proposal aims to test the hypothesis that the shape of activity across the cortex can encode shape in vision by seeing if the perception of shape can be brought about by artificially evoking shaped activity in visual cortex. I will evoke this shaped neuronal activity using optogenetics, a technique for artificially exciting neurons using light. By controlling the pattern of excitation light, I can control the shape of the activity I evoke. If I can use this optogenetic stimulation to bias macaque monkeys performing a shape discrimination task to report seeing the shapes corresponding to the artificially inserted activity, it would indicate that the brain relies on the retinotopic shape of activity across the cortex to process shape in vision. Experiments in Aim 1 will describe the behavior of macaques performing a simplified shape discrimination task and the neuronal signals recorded as they perform the task, with detailed computational modeling of potential neuronal strategies. Aim 2 will be focused on the development of the pipeline necessary for precise shaping of optogenetically evoked activity. Aim 3 will be an experiment in which optogenetics will be used to introduce artificial activity of a specific shape into the visual cortex of macaques performing the shape discrimination task. I will see if behavior, and thus likely perception, is systematically affected by the addition of artificial neuronal activity that only contains information by virtue of the shape of its spread across the cortex. The proposed work will be an important contribution to our understanding of how shape is processed in vision and will have broad implications for the utility of patterned optogenetic stimulation in translational contexts such as for use in cortical neuroprostheses for restoring vision.