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

使用图案光遗传学对灵长类动物 V1 中全球范围视觉特征的位置代码的作用进行因果测试

基本信息

批准号：
10157768
负责人：
Shun Kobayashi
金额：
$ 3.77万
依托单位：
UNIVERSITY OF TEXAS AT AUSTIN
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-01-16 至 2024-01-15
项目状态：
已结题

项目摘要

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.

人类对物体的整体形状高度敏感——这是物体识别的关键一步。大脑利用刺激诱发的活动在视觉皮层表面传播的形状来为了处理形状，利用视网膜定位——有据可查的神经元组织作为神经元的投影我们小组之前的工作发现，大脑皮层表面的视野活动的形状。皮层持有可用于解码刺激整体形状的信息，但大脑是否目前的提案旨在测试以下假设：实际使用此信息尚不清楚。皮层活动的形状可以通过观察形状的感知是否可以编码视觉中的形状是通过人工诱发视觉皮层的形状活动而产生的。我将使用光遗传学来唤起这种形状的神经元活动，这是一种使用光遗传学来人工刺激神经元的技术通过控制激发光的模式，我可以控制我引发的活动的形状。光遗传学刺激使猕猴在执行形状辨别任务时报告看到了物体与人工插入的活动相对应的形状，这表明大脑依赖于视网膜专题整个皮层活动的形状，以处理视觉中的形状。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信号，以及潜在的详细计算模型目标 2 将侧重于开发精确塑造所需的管道。目标 3 将是一个利用光遗传学引入光遗传学的实验。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。我将看看行为以及可能的感知是否受到添加人工神经系统的系统影响所提议的工作仅凭借其在大脑皮层中传播的形状来包含信息。这将为我们理解形状在视觉中的处理方式做出重要贡献，并将具有广泛的应用前景。图案化光遗传学刺激在翻译环境中的效用，例如在皮质中的使用用于恢复视力的神经假体。