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牵涉到数以千计的神经元，这些神经元有着广泛的差异 刺激的选择性和空间分布在感觉脑图上。这个组织提出了必要的 关于整合如此大量分散的神经元活动的规则的问题 产生一致的感知和可靠的行为。对感官刺激的行为反应依赖于 代表它的所有活跃神经元的加权和，或特定子群的加权和 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？虽然这些问题已经 使用各种解码方法进行了计算研究，人口之间的因果联系 活动和行为一直缺乏。这个项目将通过使用模式化的刺激来提供这样的链接 通过体内全息刺激来偏向和驱动有针对性和特征性的神经元群体 行为反应。 拟议中的实验将确定神经元之间的空间关系如何与它们的 对行为的相对影响，并评估这种空间权重如何受到刺激变化的影响 强度、信噪比和刺激复杂性。感官系统之间的比较将揭示 哪些规则是一般性的，哪些规则与特定的感官需求有关。因为感觉神经元 经过广泛的调整，每个刺激都会激活具有不同刺激偏好的神经元。这些实验将检验 共享特定刺激偏好的神经元是否具有协同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都有不同的 反映他们不同功能贡献的身份，项目将测试行为角色是否在 大脑皮层、遗传特性或投射靶点的神经元。总而言之，这些实验将 提供以前无法获得的有关刺激的编码和读出的新信息，以及如何 这些结果适用于更自然的感官刺激。

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.