MODELS OF CORRELATION BASED NEURAL DEVELOPMENT

描述(改编自申请者的摘要)： 神经发育的后期阶段是由神经元活动引导的。 指导既由活动的内在模式提供，也由活动前后的模式提供 出生，以及出生后的经验所产生的活动。理论上的 研究将解决依赖于活动的机制在 哺乳动物初级视皮层的发育。这样的大脑皮层 机制似乎在人类的许多方面都扮演着重要的角色 健康，包括视力障碍，如斜视和弱视，如 以及视网膜术后视功能的恢复和重组 损伤。理论研究将解决以下具体问题 初级视皮层发育中的问题：(1) 在视网膜桥、眼部地图之间可能发展的关系 优势、方向、差异和其他皮质感受野 属性，如首选的空间频率和空间相位，以及 这些属性之间的关系在个体接受性中发展 当输入四种类型(从左侧开始居中和偏离中心)时的字段 和右眼)竞相支配二维皮质层 代表初级视觉皮质的第四层；(2) 兴奋性神经元和抑制性神经元的感受野之间的发育 当这两种类型的神经元都包括在内时，具有现实的连接性 第四层电路的模型；(3)对这些关系的影响 皮质内的同时塑性，以及前馈 突触，以及更真实的突触可塑性和 由最近的实验工作推动的竞争。在所有这些中 研究，目标将是描述不同的可能 在依赖活动的情况下可能导致的发育结果， 基于相关性的突触可塑性机制，并确定 实验上可测量和可操纵的因素将决定 实际结果，如果这种机制是发展的基础。这将是 为假设的实验测试提供了基础 机制是所研究现象的基础，并最终得到改进 相关的人类健康问题，如斜视、弱视和 视网膜损伤。

DESCRIPTION (Adapted from applicant's abstract): Many aspects of the later stages of neural development are guided by neuronal activity. Guidance is given both by intrinsic patterns of activity, before and after birth, and by activity resulting from experience after birth. Theoretical studies will address the role of activity-dependent mechanisms in the development of the mammalian primary visual cortex. Such cortical mechanisms appear to play an important role in many aspects of human health, including visual disorders such as strabismus and amblyopia, as well as recovery and reorganization of visual function after retinal lesions. The theoretical studies will address the following specific questions in the development of the primary visual cortex: (1) The relationships that may develop between the maps of retinotopy, ocular dominance, orientation, disparity, and other cortical receptive field properties such as preferred spatial frequency and spatial phase, and the relationships among these properties that develop in individual receptive fields, when inputs of four types (ON-center and OFF-center from the left and right eyes) compete to innervate a two-dimensional cortical layer representing layer 4 of primary visual cortex; (2) The relationships that develop between the receptive fields of excitatory and inhibitory neurons when both types of neurons are included, with realistic connectivity, in the model of the layer 4 circuit; (3) The effects on these relationships of simultaneous plasticity of intracortical, as well as, feedforward synapses, and of more realistic models of synaptic plasticity and competition motivated by recent experimental work. In all of these studies, the goal will be to characterize the different possible developmental outcomes that may result under activity-dependent, correlation-based mechanisms of synaptic plasticity, and to determine the experimentally measurable and manipulable factors that will determine the actual outcome, if such mechanisms underlie development. This will provide a basis for experimental tests of the hypothesis that such mechanisms underlie the studied phenomena, and ultimately for improvements of related human health problems, such as strabismus, amblyopia, and retinal lesions.