IRFP: Signal detection in noise in the grasshopper Chorthippus biguttulus

国际研究奖学金项目使美国科学家和工程师能够在国外进行9至24个月的研究。该计划的奖励为联合研究提供了机会，并利用独特或互补的设施、专业知识和国外的实验条件。该奖项将支持Michael S. Reichert博士与Michael Greenfield博士在法国图尔昆虫生物学研究所开展为期24个月的研究。动物的交流经常发生在嘈杂的环境中，噪声对信号传输、检测和定位等重要任务施加了限制。此外，通信通常是一个多向的过程：信号可以传输到多个接收器，并且信号发送者可以相互参与相互的信号交互。尽管如此，很少有研究检查噪音对动物多向信号相互作用的影响。这项研究考察了噪音对一种参与配偶识别和定位的声学二重奏的物种的交流的影响，这种物种是欧洲蚱蜢。该物种的雄性和雌性在这些过程中都会产生并响应声音信号。本研究利用信号检测理论和对照实验的方法，考察了雄性和雌性个体以及二重唱对噪声中信号的响应，验证了噪声对多向信号的影响更强的预测，并探讨了噪声对自然通信交互的影响。本研究涉及三个具体项目。首先，通过将雄性和雌性的个体暴露在不同程度掩蔽噪声的异性合成歌曲模型中并测量个体的反应阈值，比较了雄性和雌性的信号检测能力。在第二部分中，比较了单向和二重唱信号相互作用在噪声中的信号检测，并预测二重唱信号相互作用将遭受更大程度的信号检测误差。在第三部分中，研究了不同噪音水平下雌性对交配信号的反应，以确定信号吸引力如何受到掩蔽噪音的影响。该项目的好处包括增加了对噪声对声信号检测和识别的影响的理解。被研究物种的大脑对声音的处理得到了很好的描述。因此，这个项目对简单的神经系统如何在复杂和嘈杂的环境中处理信号感知的挑战产生了新的见解。这具有广泛的意义，可以更好地理解包括人类在内的其他系统的噪音听力。除了这些好处之外，这项研究还将为PI提供重要的机会，与昆虫生物学研究所（Michael Greenfield教授）和德国柏林洪堡大学（Bernhard Ronacher教授）的主要国际研究小组开展合作。

The International Research Fellowship Program enables U.S. scientists and engineers to conduct nine to twenty-four months of research abroad. The program's awards provide opportunities for joint research, and the use of unique or complementary facilities, expertise and experimental conditions abroad.This award will support a twenty-four month research fellowship by Dr. Michael S. Reichert to work with Dr. Michael Greenfield at the Research Institute on Insect Biology in Tours, France.Animal communication often takes place in noisy environments and noise imposes constraints on the important tasks of signal transmission, detection and localization. In addition, communication is often a multi-directional process: signals can be transmitted to multiple receivers and signalers may engage in reciprocal signaling interactions with one another. Despite this, few studies have examined the effects of noise on multi-directional signaling interactions in animals. This study examines the effects of noise on communication in a species that engages in acoustic duets involved in mate recognition and localization, the European grasshopper Chorthippus biguttulus. Both males and females of this species produce and respond to acoustic signals during these processes. By using the tools of signal detection theory and controlled experiments examining the responses to signals in noise of individual males and females, as well as duetting pairs, this study tests the prediction that noise has stronger impacts on multi-directional signaling, and examines the consequences of noise on natural communication interactions.This study involves three specific projects. In the first, the signal detection abilities of males and females are compared by exposing individuals of both sexes to synthetic song models of the opposite sex in various levels of masking noise and measuring individual response thresholds. In the second, signal detection in noise is compared for unidirectional and duetting signal interactions, with the prediction that duetting interactions will suffer from greater levels of signal detection errors. In the third, assays of the response of females to mating signals under varying levels of noise are used to determine how signal attractiveness is affected by masking noise.The benefits of this project include an increased understanding of the effects of noise on acoustic signal detection and recognition. The processing of sound in the brain of the study species is well-described. Therefore, this project generates new insights on how simple nervous systems deal with the challenges of signal perception in complex and noisy environments. This has broad implications that could lead to a better understanding of hearing in noise that applies to other systems, including humans. In addition to these benefits, this research will provide the PI with important opportunities to develop collaborations with major international research groups at the Research Institute on Insect Biology (Prof. Michael Greenfield) and at Humboldt University in Berlin, Germany (Prof. Bernhard Ronacher).