SGER: Nature, Nurture, and Cortical Maps

神经科学中最基本、最长期存在的问题之一是行为模式如何影响大脑组织。这是与成人和发育中的大脑有关的经典的“先天与后天”问题。大脑组织的哪些方面是由基因决定的，或者行为能在多大程度上影响大脑组织？与该领域其他长期存在的问题一样，可以通过研究新的和有利的模型系统来取得重大进展(例如，我们对动作电位传导的理解在很大程度上要归功于巨型鱿鱼的准备，我们对听觉定位的理解很大程度上归功于谷仓猫头鹰)。将使用星鼻鼹鼠，这是一种新的特殊模型系统，用于研究脑图和行为之间的关系。在所有被研究的哺乳动物中，星鼻鼹鼠拥有最发达的触觉，这为这些研究提供了无与伦比的优势。我们的实验室在它们的大脑中发现了三个独立的、解剖学上可见的皮质地图，这些地图的大小与星鼻鼹鼠的行为模式密切相关。这种相关性是如何发展起来的？我们的研究强烈表明，行为正在积极塑造该物种的大脑地图，这反过来使星鼻鼹鼠成为研究哺乳动物大脑地图如何被经验修改的理想模型系统。由于星鼻鼹鼠皮质组织与哺乳动物和灵长类动物有如此多的共同特征，这些研究结果可以为了解大脑可塑性的一般原理提供关键的新见解。或者，如果星鼻鼹鼠具有允许成人大脑可塑性的独特机制，那么这些机制对我们理解大脑功能同样重要。我们将通过检验两个可供选择的假设来开始这些调查。首先，行为模式决定了鼹鼠的大脑图谱。第二，脑图的组织在发育过程中是固定的，不受行为的影响。这个问题将通过改变恒星在早期或成年时的发育来研究，然后跟踪由此产生的新行为模式对星鼻鼹鼠大脑模块的影响。将结合解剖学和电生理学研究以及精确量化的行为观察来研究皮质的发育和组织。这些研究的结果将引起广泛的研究人员的兴趣，说明几个一般原则。此外，该项目将包括为本科生、研究生和研究生实习生提供独特的教育机会的实地和实验室工作。发表的成果将在科学场所、普通公众和K-12学生的讲座上进行讨论，并作为Vanderbilt的“研究探索者”计划和少数族裔访问研究中心计划的一部分。

One of the most fundamental and longstanding questions in the neurosciences is how behavior patterns influence brain organization. This is the classic "Nature versus Nurture" question in relation to adult and developing brains. What facets of brain organization are genetically determined, and alternatively how much can be influenced by behavior? As with other longstanding questions in the field, major advances can be made by examining new and favorable model systems (e.g. we owe much of our understanding of action potential conduction to the giant squid preparation, and much of our understanding of auditory localization to barn owls). The star-nosed mole, a new exceptional model system for examining the relationship between brain maps and behavior will be used. Star-nosed moles have the most well-developed sense of touch of any investigated mammal, and this provides unparalleled advantages for these investigations. Our lab has discovered 3 separate and anatomically visible cortical maps in their brains that are closely correlated in size with patterns of star-nosed mole behavior. How does this correlation develop? Our studies strongly suggest that behavior is actively shaping the brain maps in this species and this in turn makes star-nosed moles an ideal model system for examining how brain maps in mammals are modified by experience. Because star-nosed mole cortical organization shares so many features in common with mammals and primates in general, results from these investigations can provide critical new insights into general principles of brain plasticity. Alternatively, if star-nosed moles have unique mechanisms for allowing adult brain plasticity, these mechanisms are equally important to our understanding of brain function. We will begin these investigations by testing two alternative hypotheses. The first is that behavior patterns are responsible for shaping the brain maps in moles. The second is that the organization of brain maps is fixed during development and unaffected by behavior. This question will be investigated by altering the development of the star at early stages or in adults, and then tracking the effect of the resulting new behavior patterns on star-nosed mole brain modules. Cortical development and organization will be investigated with a combination of anatomical and electrophysiological studies in conjunction with precisely quantified behavioral observations. Results from these studies wiill be of interest to a broad range of investigators, illustrating several general principles. In additional, this project will involve field and laboratory work for undegraduates, graduate, and post-graduate trainees providing a uniques rangeof educatinal opportunities. The published results will be discussed in scientific venues, as well as lectures to the general public and K-12 students, and as part of Vanderbilt's "Research Explorers" program and the Minority Access Research Centers Program.