Spine Dynamics Underlying Ocular Dominance Plasticity

描述（申请人提供）：在发育中的神经系统中，最初混杂的突触连接被活动依赖机制重塑，轴突加强与某些目标的连接，同时完全断开与其他目标的连接。在新皮层中，这一过程在发育中的初级视觉皮层中得到了最彻底的研究，在初级视觉皮层中，两只眼睛的活动去关联会显著降低皮层的双眼视功能。皮质生理学的这些功能变化被广泛认为是突触连接效能的长期变化。然而，突触可塑性导致皮层回路功能改变的具体机制仍不清楚。本研究的主要目的是确定首先观察到的皮层回路中双眼反应的经验依赖性变化的位置，跟踪其随时间的进展，并验证这些变化锚定在突触连通性解剖变化中的假设。为了解决这些问题，将使用双光子激光扫描显微镜、内在信号光学成像和单单元记录等技术来绘制电路可塑性并跟踪体内突触连通性的变化。

DESCRIPTION (provided by applicant): In the developing nervous system, initially promiscuous synaptic connections are remodeled by activity-dependent mechanisms, with axons strengthening their connections with some targets while completely disconnecting from others. In the neocortex, this process has been most thoroughly studied in the developing primary visual cortex, where decorrelating the activity of the two eyes dramatically reduces cortical binocularity. These functional changes in cortical physiology are widely accepted to be anchored in long-lasting changes in the efficacy of synaptic connections. However, the specific mechanisms by which synaptic plasticities lead to changes in the function of cortical circuitry remain elusive. The major objective of the work proposed here is to determine where in the cortical circuit experience-dependent changes in binocular responses are first observed, track the progression over time, and test the hypothesis that these changes are anchored in anatomical changes in synaptic connectivity. To address these questions, techniques such as 2-photon laser scanning microscopy, intrinsic signal optical imaging, and single-unit recordings, will be used to map circuit plasticity and follow changes in synaptic connectivity in vivo.