DISSERTATION RESEARCH: Assessing the Effects of Stress Physiology on Long-lasting Memory in a Free-living Animal

糖皮质激素，通常被称为“应激激素”，可以影响短期记忆的形成（即，持续数秒到数天的记忆），但压力荷尔蒙对持续数月到数年的记忆的影响尚不清楚。此外，许多记忆研究使用实验室动物，这些动物通常具有与自由生活的动物不同的行为和生理。这项研究将评估应激激素对自由生活的佛罗里达灌丛鸦的长期记忆的影响，灌丛鸦是一种长寿的鸟类，可以保留多年的记忆。更好地了解压力如何介导记忆可能会改善圈养繁殖的濒危物种的释放后生存。许多保护计划在将濒危动物释放到自然栖息地之前教导它们捕食者的危险，而对潜在捕食者身份的强烈记忆对于动物的生存至关重要。这项研究也可能对损害持久记忆的人类疾病的研究产生影响，例如创伤后应激障碍和阿尔茨海默病。此外，这项研究将为孟菲斯大学的本科生提供研究机会，其中超过40%的学生来自科学领域代表性不足的群体。压力可以通过糖皮质激素（GC）介导记忆功能，糖皮质激素在低基线浓度下释放，但在对压力源的反应中增加。例如，在学习后不久暴露于增加的循环GC水平通常会增强长期记忆的形成。长期记忆持续数小时至数周，而持续数月至数年的记忆被称为持久记忆。尽管对GC对短期和长期记忆的影响有着丰富的知识，但对GC对长期记忆的影响的理解基本上是不存在的。这项研究的目的是了解循环中的糖皮质激素如何影响情绪唤起事件的持久记忆。研究人员将在恐惧条件反射过程中操纵自由生活的佛罗里达灌丛鸦（Aphelocoma coerulescens）的GC循环水平，其中受试者将被条件反射以避免人工的，新的捕食者或暴露于无威胁的控制。然后，研究人员将测量受试者在条件反射后48小时和10个月对新捕食者的回避，以评估GC在巩固和保留联想记忆中的作用。这项研究的所有数据和分析都将在GitHub上免费提供，GitHub是一个免费的基于Web的Git存储库托管服务，网址为https://github.com/Jonesbc。

Glucocorticoids, commonly known as "stress hormones", can affect the formation of short-term memories (i.e., memories that last from seconds to days), but the effects of stress hormones on memories that persist for months to years are unknown. Additionally, many memory studies use laboratory animals, which often have different behaviors and physiologies than their free-living counterparts. This research will assess the effects of stress hormones on the long-lasting memory of free-living Florida scrub-jays, a long lived bird that retains memories for years. A better understanding of how stress mediates memory may improve the post-release survival of captive-bred endangered species. Many conservation programs teach endangered animals the dangers of predators prior to release into natural habitats, and a strong memory of the identity of potential predators is essential for an animal's survival. This research may also have impacts on the study of human disorders that impair long-lasting memory, such as post-traumatic stress disorder and Alzheimer's disease. In addition, this research will provide research opportunities for University of Memphis undergraduates, over 40% of which are from groups underrepresented in science.Stress can mediate memory function via glucocorticoids (GCs), which are released at low baseline concentrations, but increase in response to a stressor. For example, exposure to increased levels of circulating GCs shortly after learning typically enhances long-term memory formation. Long-term memories last hours to weeks, whereas memories that persist for months to years are known as long-lasting memories. Despite the robust knowledge of the effects of GCs on short- and long-term memory, the understanding of the effects of GCs on long-lasting memory is essentially nonexistent. The goal of this study is to understand how circulating glucocorticoids affect the long-lasting memory of an emotionally arousing event. The researchers will manipulate circulating levels of GCs in free-living Florida scrub-jays (Aphelocoma coerulescens) during a fear conditioning protocol wherein subjects will be either conditioned to avoid an artificial, novel predator or exposed to a non-threatening control. The researchers will then measure subjects' avoidance of the novel predator 48 hours and 10 months post-conditioning to assess the role of GCs in consolidation and retention of the associative memory. All data and analysis from this research will be made publically and freely available on GitHub, a free, web-based Git repository hosting service, at https://github.com/Jonesbc.