The neural circuitry of learning, memory, and decision-making in honey bees

西方蜜蜂（Apis mellifera）以其复杂的行为而闻名。它可以学习一天中食物可用性的时间和多个同时食物来源的可用性位置。它可以记忆和计算地标，并遵循天空中的紫外线模式（“太阳罗盘”）导航到已知的食物来源。然后，它可以回家，并通过一种称为“摇摆舞”的象征性语言将食物来源的位置传达给它的蜂巢，其中来源的方向和距离通过身体运动传达。人类利用蜜蜂来获取蜂蜜和蜂蜡已经有9000年的历史了，而在这9000年的一半时间里，人类一直在积极地驯养蜜蜂。然而，尽管亚里士多德也以养蜂而闻名，但仔细的蜜蜂实验直到世纪才开始。即使是现在，我们才刚刚开始了解任何动物行为的神经基础。神经行为学是从进化和比较的角度研究大脑结构和功能的学科。它主要关注大脑如何产生行为。由于蜜蜂的大脑对于昆虫来说非常大，大约1毫米3，包含近100万个神经元，而且蜜蜂拥有如此令人印象深刻的复杂行为，蜜蜂是神经行为学的理想研究动物。发现蜜蜂大脑如何产生行为是我研究计划的长期目标。在这个资助周期中，我的实验室将继续探索一个重要的昆虫大脑区域的组织，称为蘑菇体（MB），它涉及感觉整合，学习和记忆。我们将训练蜜蜂执行复杂的感官学习任务，并研究这些信息如何在大脑中编码。我们还将研究大脑如何因这些经历而发生变化。有有限的证据表明，学习发生在MB输入区域（肾盏）和MB输出区域（肺叶）。我们最终将了解这些信息是如何组合的，并与大脑中的其他信息流进行比较，以了解决策是如何做出的。这项工作之所以重要，有两个原因。首先，虽然昆虫的大脑不同于人类的大脑，但在很大程度上，神经元就是神经元。理解更易处理的大脑的结构和功能将指导我们试图理解人类大脑的结构和功能（以及功能丧失）。第二，传粉者的健康是目前全世界严重关注的问题。随着栖息地的丧失、杀虫剂使用的增加和新的入侵性害虫，传粉昆虫的数量几十年来一直在下降。仅蜜蜂授粉一项在加拿大就有25亿美元的产业，在全球也有2000亿美元的产业。考虑到传粉者负责我们大约三分之一的食物，解决昆虫的感觉整合，学习和决策问题至关重要，可能会导致生态系统服务的新工具，提高传粉者的效率，并可能增加作物产量。

The western honey bee (Apis mellifera) is renowned for its complex behaviour. It can learn the times of day of food availability and the locations of availability for multiple simultaneous food sources. It can memorize and count landmarks and follow UV light patterns in the sky (the "sun compass") to navigate to known food sources. It can then return home and communicate the locations of food sources to its hivemates via a symbolic language called the "waggle dance", wherein the direction and distance of the source are communicated by body movements. Humans have exploited bees for honey and wax for 9000 years and actively kept domesticated bees for half that time. However, while even Aristotle was known to keep bees, careful bee experimentation did not begin until the 18th century. Even now, we are only beginning to understand the neural underpinnings of behaviour in any animal. Neuroethology is the study of brain structure and function from an evolutionary and comparative perspective. It focuses largely on how brains produce behaviour. Because the honey bee has an unusually large brain for an insect, measuring about 1 mm3 and containing nearly 1 million neurons, and because the honey bee possesses such an impressive repertoire of complex behaviours, the honey bee is an ideal research animal in neuroethology. Discovering how honey bee brains produce behaviour is the long-term objective of my research program. In this grant cycle, my lab will continue to explore the organization of an important insect brain region called the mushroom bodies (MB), which are involved in sensory integration, learning, and memory. We will train bees to perform complicated sensory learning tasks and look at how this information is coded in the brain. We will also look at how the brain changes due to these experiences. There is limited evidence that learning occurs both in the MB input regions (the calyces) and the MB output regions (the lobes). We will ultimately learn how this information is combined and compared with other information streams in the brain to understand how decisions are made. This work is important for two reasons. First, while insect brains are different than human brains, to a large extent a neuron is a neuron. Understanding structure and function in a more tractable brain will guide us as we try to understand brain structure and function (and loss of function) in humans. Second, pollinator health is of serious concern worldwide right now. With loss of habitat, increased pesticide use, and new invasive pests, pollinator numbers have been declining for decades. Honey bee pollination alone is a $2.5 billion industry in Canada and a $200 billion industry worldwide. Considering pollinators are responsible for about a third of our food, solving problems in sensory integration, learning, and decision making in insects is critical and may lead to novel tools in ecosystem service, increasing pollinator efficiency, and possibly increasing crop yield.