Determining which neurons contribute to a particular behaviorally distinguishable percept Project

在感觉结构中，即使是最简单的刺激也会涉及成千上万的神经元，这些神经元具有广泛的变化 刺激选择性和空间分布在感觉脑地图。该组织提出了必要的 这样一个大的分散的神经元群体的活动的整合规则的问题 以产生统一的感知和可靠的行为。对感官刺激的行为反应是否依赖于 代表它的所有活跃神经元的加权和，或者代表它的所有活跃神经元的 神经元（例如，由遗传特性、刺激选择性、位置或投射目标定义）？ 此外，活跃群体中不同区域的神经元是如何加权的？虽然这些问题 使用各种解码方法进行了计算研究，人口之间的因果关系 活动和行为缺乏。这个项目将通过使用模式化的刺激来提供这样的联系， 用体内全息刺激来偏置和驱动靶向和表征的神经元群体 行为反应 拟议的实验将确定神经元之间的空间关系如何与它们之间的关系相关联。 行为的相对影响，并评估这种空间权重如何受到刺激变化的影响 强度、信噪比和刺激复杂度。感官系统之间的比较将揭示 哪些规则是通用的，哪些规则与特定的感官需求有关。因为感觉神经元 每一种刺激都会激活具有不同刺激偏好的神经元。实验将测试 共享特定刺激偏好的神经元是否具有合作效应，以及这种权重如何 受信噪比变化的影响。最后，因为每个大脑区域的神经元有不同的 反映其不同功能贡献的身份，该项目将测试行为角色是否在 神经元跨皮层层，遗传身份，或投射目标。总的来说，这些实验 提供了新的和以前无法获得的信息编码和读出的刺激，以及如何 这些结果推广到更自然的感官刺激。

Within sensory structures, even the simplest stimulus engages thousands of neurons that have widely varying stimulus selectivity and are spatially distributed in sensory brain maps. This organization raises the essential question of the rules governing the integration of the activity of such a large dispersed population of neurons to produce uniform percepts and reliable behaviors. Do behavioral responses to a sensory stimulus rely on a weighted sum of all active neurons that represent it, or a weighted sum of particular subpopulations of neurons (for example, defined by genetic identity, stimulus selectivity, location, or projection targets)? Moreover, how are neurons in different regions of an active population weighted? While these issues have been computationally investigated using a variety of decoding approaches, the causal link between population activity and behavior has been lacking. This project will provide such links by using patterned stimulation of targeted and characterized neuronal populations with in vivo holographic stimulation to bias and drive behavioral responses. The proposed experiments will determine how the spatial relationships between neurons relate to their relative impact on behavior, and assess how this spatial weighting is affected by changes in stimulus intensity, signal-to-noise ratio, and stimulus complexity. Comparisons between sensory systems will reveal which rules are general, and which are related to particular sensory demands. Because sensory neurons are broadly tuned, every stimulus activates neurons with different stimulus preferences. The experiments will test whether neurons that share a particular stimulus preference have cooperative effects and how this weighting is affected by variation in signal-to-noise ratio. Finally, because neurons in each brain area have different identities that reflect their different functional contributions, the project will test if behavioral roles vary between neurons across cortical layers, genetic identities, or projection targets. Collectively, these experiments will provide new and previously unattainable information about the encoding and readout of stimuli as well as how those results generalize to more natural sensory stimuli.