Identifying Neurosensory Solutions to the Binding Problem in Animal Behavior

人类和动物的行为是由连续的、往往是复杂的感官输入来指导的。神经系统必须解析这个输入流，并将与环境中实际对象相对应的那些片段绑定在一起。举个例子，考虑一下停止命令。人类的视觉系统毫不费力地将一个带有红色的八角形绑定到一个统一的视觉感知中，从而引发停止行为。同样，口语单词“Stop”中的不同声音被绑定到一种听觉感知中，这也引发了停止行为。了解神经系统如何解决这些所谓的“绑定问题”的努力推动了认知和计算神经科学领域的发展。相比之下，关于非人类动物如何创造与动物感兴趣的各种事物(如猎物、捕食者、配偶、通讯信号)相对应的绑定知觉，我们知道的要少得多。因此，关于允许动物解决约束性问题的大脑机制，重要的知识空白仍然存在。该项目结合了行为学和电生理学实验，以揭示动物模型中听觉知觉绑定的一般机制，对该动物模型来说，在嘈杂的社会环境中进行声音交流是成功繁殖的关键。这项研究很重要，因为使动物能够解决听觉绑定问题的神经感觉机制的基本知识可以帮助改进听力假体和语音识别系统，从而使社会受益，这些系统在嘈杂的声学场景中表现不佳。这项研究还将回答神经系统如何塑造交流行为进化的新问题。此外，该项目将为至少15名本科生创造研究经验，推进博士后学者的培训，并将研究和教学与针对大城市地区小学生的公共宣传相结合。该项目调查了绿色树蛙(Hyla Cinerea)的听觉绑定，Hyla cinerea是听力和声音交流研究中的著名动物模型。目标1使用行为实验来识别促进听觉绑定的线索。两个实验将检验这一假设，即同步发音/偏置、共同空间起源和调和相关功能将发声频谱的不同部分结合在一起，类似于人类元音中的共振峰。目的2利用听觉中脑单个神经元的电生理记录来确定听觉绑定的神经关联。三个实验将检验这一假设，即对光谱组合敏感的神经元反应的变化与响应来自目标1的听觉绑定线索的操作而做出的行为决定的变化相关。

Human and animal behavior is guided by continuous and often complex sensory input. Nervous systems must parse this input stream and bind together those pieces corresponding to actual objects in the environment. As an illustration, consider the command to STOP. The human visual system effortlessly binds an octagonal shape with red coloration into a unified visual percept that elicits stopping behavior. Likewise, different sounds in the spoken word "stop" become bound into an auditory percept that also elicits stopping behavior. Efforts to understand how nervous systems solve these so-called "binding problems" have advanced the fields of cognitive and computational neuroscience. By comparison, much less is known about how nonhuman animals create bound percepts that correspond to the variety of things of interest to animals (e.g. prey, predators, mates, communication signals). Hence, important knowledge gaps remain concerning the brain mechanisms that allow animals to solve binding problems. This project integrates behavioral and electrophysiological experiments to uncover general mechanisms of auditory perceptual binding in an animal model for which vocal communication in noisy social environments is key to successful reproduction. This research is important because basic knowledge of neurosensory mechanisms that enable animals to solve auditory binding problems could benefit society by helping to improve hearing prosthetics and speech recognition systems, which perform poorly in noisy acoustic scenes. This research will also lead to answering new questions about how neural systems shape the evolution of communication behaviors. In addition, the project will create research experiences for a minimum of 15 undergraduates, advance the training of a postdoctoral scholar, and integrate research and teaching with public outreach aimed at elementary school kids in a large metropolitan area. The project investigates auditory binding in green treefrogs (Hyla cinerea), a well-known animal model in studies of hearing and sound communication. Aim 1 uses behavioral experiments to identify cues that promote auditory binding. Two experiments will test the hypothesis that synchronous onsets/offsets, common spatial origin, and harmonic relatedness function to bind together separate parts of the frequency spectrum of vocalizations analogous to formants in human vowel sounds. Aim 2 involves electrophysiological recordings from single neurons in the auditory midbrain to identify neural correlates of auditory binding. Three experiments will test the hypothesis that changes in the responses of neurons sensitive to spectral combinations correlate with changes in the behavioral decisions made in response to manipulations of the auditory binding cues from Aim 1.