Collaborative Research: Investigation of Odor-triggered Neuronal Dynamics and Experience-induced Olfactory Learning

该研究项目将揭示神经网络机制，使动物能够识别并学习识别动态环境中的不同气味。天蛾嗅觉系统的早期阶段产生的气味特异性反应是时空复杂的。电生理学实验，结合条件反射试验，将进行，以确定哪些功能的复杂的反应实际上是相关的蛾的自适应编码的嗅觉环境，以及如何重新雕刻这些功能时，蛾学会欣赏一种新的气味。具体来说，我们将直接实验测量（a）与气味反应在天蛾的触角叶和其他突触中心，包括侧前脑和蘑菇体，和（B）在这些结构的可塑性诱导的转变条件反射范式。这些实验将促进神经元网络的计算和理论模型的发展。具体来说，我们将开发（c）一个大规模的尖峰网络模型的天蛾嗅觉系统，将基准使用上述实验，和（d）一个理论框架，能够分析丰富的动态发现这些网络。最近大量的实验表明，昆虫以及其他动物，如哺乳动物，灵长类动物和人类，表现出大脑状态是令人难以置信的丰富，有些是由刺激直接引起的，有些是由学习过程产生的，所有这些都具有各种尺度上的动态特性。这些动态机制的复杂性仍然是一个谜。我们目前还不知道这些大脑状态能够做什么，也不知道它们如何用于驱动决策或学习。天蛾的大脑比人类的简单得多，但它的嗅觉系统与我们的嗅觉系统并没有太大的不同。通过研究这种动物的神经网络动力学、行为和学习之间的联系，我们将得出与我们的一些基本认知功能相关的结论。

This research project will uncover neuronal network mechanisms that allow animals to recognize, and learn to recognize, different odors in their dynamic environment. The early stages of the hawkmoth Manduca sexta's olfactory system generate odor-specific responses which are spatiotemporally complex. Electrophysiological experiments, in conjunction with conditioning trials, will be carried out to determine which features of the complex response are in fact relevant to the moth's adaptive encoding of its olfactory environment, and how these features are resculpted when the moth learns to appreciate a new odor. Specifically, we will direct experiments measuring (a) high-order dynamical structures associated with odor-response in the hawkmoth's antennal lobe and other synaptic centers including the lateral protocerebrum and mushroom bodies, and (b) the plasticity-induced shift in these structures following a conditioning paradigm. These experiments will facilitate development of both computational and theoretical models of neuronal networks. Specifically, we will develop (c) a large-scale spiking network model of the hawkmoth olfactory system which will be benchmarked using the experiments mentioned above, and (d) a theoretical framework capable of analyzing the rich dynamics found in these networks.An abundance of recent experiments indicate that insects as well as other animals such as mammals, primates and humans, exhibit brain states that are incredibly rich, some directly induced by stimuli and some born from learning processes, all possessing dynamic properties on a variety of scales. The intricacies of these dynamic regimes are still a mystery. We currently do not know what these brain states are capable of, nor how they are used to drive decision making or learning. The hawkmoth -- "Manduca sexta" -- has a brain which is considerably simpler than a human's, but nevertheless has an olfactory system not too dissimilar from our own. By investigating the link between neuronal network dynamics, behavior and learning within this animal, we will draw conclusions relevant to some of our basic cognitive functions.