SGER: Nature, Nurture, and Cortical Maps

神经科学中最基本和长期存在的问题之一是行为模式如何影响大脑组织。这是一个经典的“先天vs后天”的问题，与成人和发育中的大脑有关。大脑组织的哪些方面是由基因决定的，又有多少是受行为影响的？与该领域其他长期存在的问题一样，通过检查新的和有利的模型系统可以取得重大进展（例如，我们对动作电位传导的理解很大程度上归功于巨型鱿鱼的准备，以及我们对听觉定位的理解很大程度上归功于仓鸮）。星鼻鼹鼠是一种新的特殊模型系统，用于研究大脑地图和行为之间的关系。星鼻鼹鼠拥有所有被调查的哺乳动物中最发达的触觉，这为这些调查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3个独立的解剖学上可见的皮层图，它们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的呢？我们的研究强烈表明，行为积极地塑造了这个物种的大脑地图，这反过来又使星鼻鼹鼠成为一个理想的模型系统，用于研究哺乳动物的大脑地图是如何被经验修改的。因为星鼻鼹鼠的皮质组织与哺乳动物和灵长类动物有很多共同的特征，这些研究的结果可以为大脑可塑性的一般原理提供重要的新见解。或者，如果星鼻鼹鼠有独特的机制来允许成年人的大脑可塑性，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，行为模式负责塑造鼹鼠的大脑地图。第二，大脑地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早期或成年星鼻鼹鼠的发育来研究，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发育和组织。这些研究的结果将引起广泛研究者的兴趣，说明了几个一般原则。此外，该项目还将为本科生、研究生和研究生学员提供实地和实验室工作，提供一系列独特的教育机会。发表的结果将在科学场所进行讨论，也将在公众和K-12学生的讲座中进行讨论，并作为范德比尔特大学“研究探险家”计划和少数民族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.