Neuroethology of songbird acoustic communication

我的研究项目旨在了解鸣禽声音交流的认知、感知、进化、发育和神经基础。具体来说，我目前的目标是确定控制鸣禽对其呼叫和歌曲中包含的自然声音类别（即音符类型，呼叫类型）的感知的近似机制，作为实现全面理解鸣禽声音交流这一最终目标的第一步。分类感知是一种强大的现象，在包括人类和鸣禽在内的许多动物物种中都得到了证明。通过将大量的环境刺激（如鸣禽的叫声）分类到感知类别中，而不是记忆每一个新的实例，动物可以迅速适应新的环境刺激。例如，山雀群在听到另一群“chick-a-dee”的叫声后，会迅速增加它们的叫声，减少它们的觅食活动。重要的是，它们这样做不需要了解特定的呼叫或发出呼叫的群体。相反，山雀会迅速将这种叫声归类为“外来鸟群”，并对感知到的威胁做出适当的反应。鸣禽不仅产生和感知这些自然类别，而且鸣禽也为研究类别感知提供了一个很好的模型系统；众所周知，控制声音产生和感知的大脑区域和回路是鸣禽在野外的感知能力和行为。为了开始理解鸣禽的声音类别感知，以及更广泛地理解鸣禽的声音交流，我采取了一种综合的方法，结合生物声学分析、现场回放实验和操作性条件反射实验，以及发育、神经生理学和神经解剖学的方法来确定几种鸣禽是如何感知它们的声音的。总的来说，这个研究项目不仅会增加我们对鸣禽交流、感知和认知的理解，而且会为动物如何使用声音交流提供一般的见解。

My research program is aimed at understanding the cognitive, perceptual, evolutionary, developmental, and neural bases underlying vocal communication in songbirds. Specifically, my current aim is to determine the proximate mechanisms controlling songbirds' perception of the natural vocal categories (i.e., note-types, call types) contained in their calls and songs, as a first step towards this ultimate goal of developing comprehensive understanding songbird acoustic communication. The perception of categories is a powerful phenomenon that has been demonstrated in many animal species, including humans and songbirds. By sorting large numbers of environmental stimuli, such as songbird vocalizations, into perceptual categories rather than memorizing each new instance, animals can quickly adapt to novel environmental stimuli. For example, chickadee flocks rapidly increase their calling and decrease their foraging activities after hearing another flock's 'chick-a-dee' call. Importantly, they do so without having to learn about the particular call or the flock emitting the call. Rather, chickadees quickly sort the call into a "foreign flock" category and respond appropriately to the perceived threat. Not only do songbirds produce and perceive these natural categories, but songbirds also represent an excellent model system for studying category perception; the brain areas and circuits controlling vocal production and perception are well known as are songbirds' perceptual abilities and behaviour in the wild. In order to begin to understand vocal category perception in songbirds specifically, and in so doing of songbird vocal communication more generally, I take an integrative approach and combine bioacoustic analyses, field playback experiments, and operant conditioning experiments, along with developmental, neurophysiological and neuroanatomical approaches to determine how several species songbirds perceive their vocalizations. Taken together, this research program will increase our understanding not only of songbird communication, perception and cognition but will provide general insights into how animals in general use acoustic communication.