Rodent ultrasonic vocalizations: behavioural significance

啮齿动物超声波发声：行为意义

• 批准号: RGPIN-2019-04860
• 负责人: Clarke, Paul
• 金额: $ 2.4万
• 依托单位: McGill University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=762101
• 关键词: Rodent; ultrasonic; vocalizations; behavioural; significance

Rats make many sounds beyond our hearing range. These ultrasonic vocalizations (USVs) appear to be used for communication with other rats, and we have discerned more than a dozen types of USVs. Different kinds of vocalizations predominate in different situations, and certain specific USVs may even reveal when a rat is experiencing positive or negative emotion. Traditionally, it has been thought that rodent's emotions are largely unknowable, primarily because rodents, unlike humans, cannot self-report. However, USVs seem to offer exactly this possibility, making them potentially unique among behavioural measures. Our MAIN GOAL is therefore to better understand what these various kinds of ultrasonic vocalizations signify, and how rats use them to communicate with other rats. So far, we have categorized USVs based on their acoustic properties, but we cannot be sure that rats would categorize these calls the same way as us. Therefore, we will identify which types of calls rats find attractive or aversive (Project 1). Next, we will investigate whether rats can discriminate between different call types when these calls are arranged to signal the availability of reward (Project 2). We will also explore whether some USVs help rats to avoid aggression or to establish social hierarchies (Projects 3 and 4). In particular, we hypothesize that submissive animals use a particular kind of USV ("flat" call) to signal appeasement/submission. To test this, we will study rats in an aggressive context or when competing for food. In Project 5, we will extend our research to mice. Despite a burgeoning literature, there has been very little research into whether any specific call types reflect the mice's emotional state. Therefore, guided by our recent studies of rat USVs, we will investigate whether the administration of rewarding or aversive drugs promotes particular types of call. Devocalization studies can help to establish how and when rodent ultrasonic calls are used for communication. However, this approach currently requires laryngeal nerve section, which is irreversible and causes undesirable side-effects. Project 6 therefore seeks to develop methods to transiently devocalize animals using chemogenetic and optogenetic approaches. Conceptually, this research is part of my larger aim to understand how different aspects of "reward" (positive emotions, positive reinforcement, etc) interrelate. In the longer term, our research could lead to several practical benefits. For example, if ultrasonic vocalizations do indeed reveal different emotional states, they could provide a useful and novel approach for studies linking brain activity to emotions such as pleasure and distress. It may also be possible to use specific types of USVs in order to screen for novel drug therapies for depression and chronic pain, for example. Lastly, this basic research may one day lead to more effective and humane methods for controlling rodent populations that ravage food supplies.

老鼠会发出许多我们听不到的声音。这些超声波发声（USV）似乎用于与其他大鼠交流，我们已经识别出十几种类型的USV。在不同的情况下，不同种类的发声占主导地位，某些特定的USV甚至可以揭示大鼠何时经历积极或消极的情绪。传统上，人们认为啮齿动物的情绪在很大程度上是不可知的，主要是因为啮齿动物不像人类，不能自我报告。然而，USV似乎恰恰提供了这种可能性，使其在行为措施中具有潜在的独特性。因此，我们的主要目标是更好地了解这些不同种类的超声波发声意味着什么，以及老鼠如何使用它们与其他老鼠交流。到目前为止，我们已经根据它们的声学特性对USV进行了分类，但我们不能确定老鼠会像我们一样对这些声音进行分类。因此，我们将确定哪些类型的呼叫大鼠找到吸引力或厌恶（项目1）。接下来，我们将研究大鼠是否可以区分不同的呼叫类型，当这些呼叫被安排为奖励的可用性信号时（项目2）。 我们还将探讨一些USV是否有助于大鼠避免攻击或建立社会等级（项目3和4）。特别是，我们假设，顺从的动物使用一种特殊的USV（“平”的呼叫）信号绥靖/提交。为了验证这一点，我们将研究处于攻击性环境或竞争食物的大鼠。在项目5中，我们将把研究扩展到小鼠。尽管有大量的文献，但很少有研究表明任何特定的呼叫类型是否反映了小鼠的情绪状态。因此，在我们最近对大鼠USV的研究的指导下，我们将研究奖励性或厌恶性药物的给药是否会促进特定类型的呼叫。离域研究可以帮助确定如何以及何时啮齿动物超声波呼叫用于通信。然而，这种方法目前需要喉神经部分，这是不可逆的，并导致不希望的副作用。因此，项目6寻求开发使用化学遗传学和光遗传学方法使动物暂时离域的方法。从概念上讲，这项研究是我更大目标的一部分，即理解“奖励”的不同方面（积极情绪，积极强化等）是如何相互关联的。从长远来看，我们的研究可能会带来一些实际好处。例如，如果超声波发声确实揭示了不同的情绪状态，它们可以为研究大脑活动与快乐和痛苦等情绪之间的联系提供一种有用的新方法。例如，也可以使用特定类型的USV来筛选用于抑郁症和慢性疼痛的新型药物疗法。最后，这项基础研究可能有一天会导致更有效和更人道的方法来控制破坏食物供应的啮齿动物种群。