Collaborative Research: Co-evolution of Communication Signals with Central Sensory Processing Mechanisms

为了理解感觉输入如何引导行为，重要的是要确定感觉信号的结构，编码这些信号的大脑活动模式以及动物感知它们的能力是如何相关的。 我们仍然不理解将特定神经反应特性与行为相关信号结构联系起来的一般原理。这个项目将通过比较大脑如何编码通信信号来解决这个问题，几种密切相关的电鱼在它们的信号中显示出关键的差异。该项目将使用神经生理学实验，行为分析和信号分析来研究大脑机制如何优化物种特异性信号特性，以及这些神经机制如何影响动物感知信号的能力。该项目将测试通信信号的结构和神经反应的模式在物种之间有效匹配的假设，以便能够检测和/或区分同种信号。该模型系统，弱电鱼类的通信信号，是一个理想的平台，连接进化，神经生理学和计算方法，以了解行为的神经基础。 此外，电鱼使用“第六感”来探测它们的世界和交流是一个迷人的现象，可以吸引公众对动物多样性和神经生物学的兴趣。该项目将培训高中生、本科生和研究生。研究人员还将与K-12教师合作，制定与该项目相关的课程计划。交流信号通常随着外围感觉过滤器的进化而进化，以优化物种特异性信号的捕获。然而，关于中枢感觉回路如何进化以有效地提取和分析同种信号的复杂特征，人们知之甚少。本计画将以弱电鱼的沟通讯号与感觉系统作比较研究，探讨讯号结构、感觉处理的神经机制与知觉作业之间的关系。中心假设是，感官编码和信号结构共同进化的感知需求，允许有效的检测和识别同种信号。该项目将首先分析两个通信信号结构的跨物种变化如何影响信号的显著性。然后，该项目将使用体内电生理学来比较中枢感觉神经元的编码策略如何与跨物种的信号结构相关。最后，行为测试将量化信号结构和感觉编码策略如何影响鱼检测和区分信号的能力。因此，该项目明确地将信号多样性，感觉系统和行为联系起来。该项目具有很强的潜力，通过揭示物种特异性信号的复杂特征如何与神经编码策略及其完成的感觉任务相适应，为研究通信系统的机制和进化开辟了新的方向。CoPI将利用该项目的跨学科方法以及动物模型的魅力和吸引力，提供从K-12到高级研究生水平的推广和教育机会。

To understand how sensory inputs can guide behavior, it is important to identify how the structure of sensory signals, the patterns of brain activity that encode these signals, and the abilities of animals to perceive them are related. We still do not understand the general principles that link specific neural response properties with the structure of behaviorally relevant signals. This project will address this question by comparing how the brain encodes communication signals several closely related species of electric fish that display key differences in their signals. The project will use neurophysiological experiments, behavioral assays, and signal analysis to ask how brain mechanisms are optimized to species-specific signal properties and how these neural mechanisms influence the ability of the animals to perceive signals. The project will test the hypothesis that the structure of communication signals and the patterns of neural responses are efficiently matched across species to enable to detect and/or the discriminate conspecific signals. The model system, the communication signals of weakly electric fishes, is an ideal platform to link evolutionary, neurophysiological, and computational approaches to understanding the neural basis of behavior. Furthermore, electric fishes' use of a "sixth sense" to detect their world and communicate is a fascinating phenomenon that can engage public interest in animal diversity and neurobiology. The project will train high school, undergraduate, and graduate students. The researchers will also work with K-12 teachers to develop lesson plans that are linked to the project?s research and that are aligned with the learning goals of the AP Biology curriculum.Communication signals often evolve with peripheral sensory filters to optimize species-specific signal capture. Much less is known, however, about how central sensory circuits evolve to efficiently extract and analyze complex features of conspecific signals. This project will comparatively study the communication signals and sensory systems of weakly electric fish to investigate relationships between signal structure, neural mechanisms of sensory processing, and perceptual tasks. The central hypothesis is that sensory coding and signal structure co-evolve in response to perceptual demands to permit efficient detection and discrimination of conspecific signals. The project will first analyze how cross-species variation in the structure of two communication signals that impinge on the same sensory channel influences the conspicuousness of signals. The project will then use in vivo electrophysiology to compare how the coding strategies of central sensory neurons are related to the structure of signals across species. Finally, behavioral tests will quantify how signal structure and sensory coding strategies influence the abilities of the fish to detect and discriminate signals. The project thus explicitly links signal diversity, sensory systems, and behavior. This project has strong potential to open a new direction in studying the mechanisms and evolution of communication systems by revealing how complex features of species-specific signals are co-adapted with neural coding strategies and the sensory tasks they accomplish. The CoPIs will take advantage of the interdisciplininary approaches of the project and the charismatic and engaging nature of the animal model to provide outreach and educational opportunities from the K-12 to advanced graduate levels.