Neuroplasticity in songbirds: how changing behaviour and experience affect learning and the brain

鸣禽的神经可塑性：行为和经验的变化如何影响学习和大脑

• 批准号: RGPIN-2018-04060
• 负责人: Phillmore, Leslie
• 金额: $ 4.23万
• 依托单位: Dalhousie 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=764312
• 关键词: Neuroplasticity; songbirds; how; changing; behaviour

Over the course of a year, animals must change their behaviour in response to their changing environment. For example, birds use changes in day length or availability of resources as a cue to tell them when to breed or when not to breed. Animals must also adapt their behaviour to different situations on a daily basis: females may hear and evaluate a potential mate and learn to respond to that male's vocalizations. In order to change behaviour, the brain must have the potential and capacity to change as well. It is therefore important to measure how environmental change affects the brain. My research program aims to understand the neuroplasticity that occurs in response to the environment resulting in appropriate behavioural response. To do this, I study how both breeding condition (the physiological state of animal as ready to breed or not) and learning affect the brain of two species of songbirds: black-capped chickadees and zebra finches. Black-capped chickadees are seasonal breeders they respond to changes in day length, and in turn their behaviour and brains change with the season. In spring when in breeding condition, they sing more songs and regions in their brain important for song are larger than when they are in non-breeding condition. In winter, when in non-breeding condition, they spend a lot of time hiding and retrieving seeds (a task requiring spatial learning memory for “where”) and the hippocampus, a brain region critical for spatial memory, has more new neurons (neurogenesis) than at other times of year. One study I will perform will be to determine whether performing a task appropriate to the season (discriminating among songs when in breeding condition, remembering where seeds are hidden when in non-breeding condition) helps more new neurons live longer than when performing a task not appropriate to the season. This will tell us whether breeding condition, learning, or both affect neuroplasticity.Zebra finches are opportunistic breeders they respond to changes in resource availability, however much less is known about how their brains change depending on breeding condition. I will study how neural activity and neurogenesis (cell birth and survival) are affected by breeding condition in zebra finches by exposing some birds to resources such as a mate and nesting materials and comparing their brains to those without resources. I will also study whether exposure to a difficult learning task promotes neurogenesis compared to birds that do not perform a cognitively enriching task, to determine whether active learning helps more new neurons live longer.I will integrate the results of my experiments to achieve my long-term goal of determining how behavioural change in response to internal (breeding condition) and external factors (experience) affect neuroplasticity. My results have the potential to impact understanding of behavioural and neuroplasticity in songbirds and other organisms.

在一年的过程中，动物必须改变它们的行为来应对不断变化的环境。例如，鸟类利用白天长度的变化或资源的可用性作为提示，告诉它们何时繁殖，何时不繁殖。动物还必须每天根据不同的情况调整自己的行为：雌性可能会听到并评估潜在的伴侣，并学会对雄性的声音做出反应。为了改变行为，大脑也必须有改变的潜力和能力。因此，测量环境变化如何影响大脑是很重要的。我的研究项目旨在了解在对环境做出反应时产生的神经可塑性，从而产生适当的行为反应。为此，我研究了繁殖条件（动物准备繁殖或不准备繁殖的生理状态）和学习如何影响两种鸣禽的大脑：黑顶山雀和斑马雀。黑冠山雀是季节性繁殖动物，它们对白天长度的变化做出反应，反过来，它们的行为和大脑也会随着季节的变化而变化。在春天，当它们处于繁殖期时，它们会唱更多的歌，大脑中负责鸣叫的区域也比非繁殖期大。在冬季，在非繁殖条件下，它们花很多时间隐藏和检索种子（一项需要空间学习记忆“在哪里”的任务），海马体，一个对空间记忆至关重要的大脑区域，比一年中的其他时候有更多的新神经元（神经发生）。我将进行的一项研究将是确定执行适合季节的任务（在繁殖条件下区分歌曲，在非繁殖条件下记住种子隐藏的位置）是否比执行不适合季节的任务能帮助更多的新神经元活得更长。这将告诉我们是否繁殖条件，学习，或两者都影响神经可塑性。斑胸草雀是机会主义的繁殖者，它们对资源可用性的变化做出反应，然而，人们对它们的大脑如何根据繁殖条件发生变化知之甚少。我将研究斑马草雀的神经活动和神经发生（细胞出生和存活）如何受到繁殖条件的影响，方法是将一些鸟类暴露在配偶和筑巢材料等资源中，并将它们的大脑与没有资源的鸟类进行比较。我还将研究与不执行认知丰富任务的鸟类相比，暴露于困难的学习任务是否会促进神经发生，以确定主动学习是否有助于更多的新神经元活得更长。我将整合我的实验结果，以实现我的长期目标，即确定行为变化对内部（繁殖条件）和外部因素（经验）的反应如何影响神经可塑性。我的研究结果有可能影响对鸣禽和其他生物的行为和神经可塑性的理解。