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

为了了解感觉输入如何指导行为，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的神经反应属性与行为相关信号的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信号上显示出关键的差异。该项目将使用神经生理学实验、行为分析和信号分析来询问大脑机制如何针对物种特定的信号属性进行优化，以及这些神经机制如何影响动物感知信号的能力。该项目将检验这样一个假设，即通信信号的结构和神经反应的模式在不同物种之间是有效匹配的，以便能够检测和/或区分同种信号。该模型系统是弱电鱼类的通讯信号，是一个理想的平台，将进化、神经生理学和计算方法联系起来，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种令人着迷的现象，可以引起公众对动物多样性和神经生物学的兴趣。该项目将培养高中生、本科生和研究生。研究人员还将与K-12教师合作，制定与S研究项目相关的教案，并与AP生物学课程的学习目标保持一致。交流信号通常与外围感官过滤器一起进化，以优化特定物种的信号捕获。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，我们知道的要少得多。本项目将对弱电鱼类的通讯信号和感觉系统进行比较研究，以探讨信号结构、感觉加工的神经机制和知觉任务之间的关系。中心假设是，感觉编码和信号结构共同进化，以响应感知需求，从而实现对同种特定信号的有效检测和区分。该项目将首先分析两个影响同一感觉通道的通信信号结构的跨物种差异如何影响信号的显着性。然后，该项目将使用活体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。该项目揭示了物种特有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协同适应，从而为研究通信系统的机制和进化开辟了新的方向。COPIS将利用该项目的跨学科方法和动物模型的魅力和吸引人的性质，提供从K-12到高级研究生水平的外联和教育机会。

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.