Neural Basis of Behavioral Arousal

项目摘要 许多神经网络动态地从一种活动类型转换到另一种活动类型。大多数研究旨在 确定如何在电路或细胞/分子水平上进行任务切换强调了 启动一种类型的活动并终止另一种活动的过程。这项研究的目标往往更高 “秩序”或类似命令的神经元。我们的研究表明，这种方法有局限性。因此， 任务切换的动态受网络响应变化的能力的影响很大 ‘命令’。我们研究的电路与许多其他电路的相似之处在于其活动被配置和重新配置 通过调节神经递质，发挥持久的影响，并创造一种隐含的记忆形式。一个 我们的研究解决了一个重要的一般性问题：持续调制将如何影响任务切换？ 我们在两种“对抗性”马达之间切换的情况下解决这个问题 程序。对任务转换的初步研究描述了一种存在“负面”影响的情况，即， 神经调节的持续效应使人们不可能立即完成转换任务。这是‘任务切换成本’ 是在这样一种情况下观察到的，在这种情况下，它可能是有益的。也就是说，我们证明了一种进食 反复生成兴奋运动程序的网络无法快速切换和生成 胃肠道运动活动。本申请中提出的研究解决了一个新问题；是否存在以下情况 哪种持续的神经调节能起到相反的作用，并对任务切换“有利”？已被占用 以往和初步的数据有力地表明，这个问题的答案是肯定的。建议 实验旨在寻求对这一想法的进一步支持。从广义上讲，我们的研究将提供 可以促进或阻碍任务切换的电路和细胞/分子机制。这些机制 是相当普遍的兴趣，因为任务切换对于大多数物种(包括人类)来说是必不可少的 应对外部环境的变化。

Project Summary Many neural networks dynamically transition from one type of activity to another. Most studies designed to determine how task switching occurs at the circuit or cellular/molecular level have emphasized the `decision making' process that initiates one type of activity and terminates another. This research often targets `higher order' or command-like neurons. Our research demonstrates that this approach has limitations. Thus, the dynamics of task switching can be greatly impacted by the ability of a network to respond to a change in `command'. The circuit that we study is similar to many others in that its activity is configured and reconfigured by modulatory neurotransmitters that exert effects that persist and create an implicit form of memory. An important general question our research addresses is; how will persistent modulation impact task switching? We address this question in the situation where the switch is between two types of `antagonistic' motor programs. Initial studies of task switching characterized a situation where there was a `negative' effect, i.e., persistent effects of neuromodulation made it impossible to task switch immediately. This `task switch cost' was observed in a situation in which it is presumably beneficial. Namely, we demonstrated that a feeding network that had repeatedly generated egestive motor programs could not rapidly switch and generate ingestive motor activity. Research proposed in this application addresses a new issue; is there a situation in which persistent neuromodulation can have the opposite effect and be `beneficial' for task switching? Taken together previous and preliminary data strongly suggest that the answer to this question is yes. Proposed experiments are designed to seek further support for this idea. In broad terms our research will provide insight into circuit and cellular/molecular mechanisms that can facilitate or impede task switching. These mechanisms are of considerable general interest since task switching is essential for most species (including humans) to cope with changes in the external environment.