...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>The Journal of Neuroscience: The Official Journal of the Society for Neuroscience >Motor Cortex Maturation Is Associated with Reductions in Recurrent Connectivity among Functional Subpopulations and Increases in Intrinsic Excitability
【24h】

Motor Cortex Maturation Is Associated with Reductions in Recurrent Connectivity among Functional Subpopulations and Increases in Intrinsic Excitability

机译：运动皮层成熟与功能亚群之间的经常性连接减少和内在兴奋性增加相关

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Behavior is derived from the configuration of synaptic connectivity among functionally diverse neurons. Fine motor behavior is absent at birth in most mammals but gradually emerges during subsequent postnatal corticospinal system maturation; the nature of circuit development and reorganization during this period has been largely unexplored. We investigated connectivity and synaptic signaling among functionally distinct corticospinal populations in Fischer 344 rats from postnatal day 18 through 75 using retrograde tracer injections into specific spinal cord segments associated with distinct aspects of forelimb function. Primary motor cortex slices were prepared enabling simultaneous patch-clamp recordings of up to four labeled corticospinal neurons and testing of 3489 potential synaptic connections. We find that, in immature animals, local connectivity is biased toward corticospinal neurons projecting to the same spinal cord segment; this within-population connectivity significantly decreases through maturation until connection frequency is similar between neurons projecting to the same (within-population) or different (across-population) spinal segments. Concomitantly, postnatal maturation is associated with a significant reduction in synaptic efficacy over time and an increase in intrinsic neuronal excitability, altering how excitation is effectively transmitted across recurrent corticospinal networks. Collectively, the postnatal emergence of fine motor control is associated with a relative broadening of connectivity between functionally diverse cortical motor neurons and changes in synaptic properties that could enable the emergence of smaller independent networks, enabling fine motor movement. These changes in synaptic patterning and physiological function provide a basis for the increased capabilities of the mature versus developing brain.
机译：行为源自功能多样的神经元之间的突触连通性的配置。大多数哺乳动物在出生时就没有精细的运动行为，但在随后的出生后皮质脊髓系统成熟过程中逐渐出现。在此期间，电路开发和重组的性质尚未得到充分探索。我们从出生后第18天到第75天，使用逆行示踪剂注射到与前肢功能不同方面相关的特定脊髓节段中，研究了Fischer 344大鼠从功能上不同的皮质脊髓种群之间的连通性和突触信号传导。准备了初级运动皮层切片，可以同时记录最多四个标记的皮质脊髓神经元的膜片钳记录，并测试3489个潜在的突触连接。我们发现，在未成熟的动物中，局部连通性偏向投射到同一脊髓节段的皮质脊髓神经元。这种人口内部连通性会随着成熟而显着降低，直到投射到相同（人口内部）或不同（跨人口）脊柱节段的神经元之间的连接频率相似。伴随地，出生后的成熟与突触效力随时间的显着降低和内在神经元兴奋性的增加相关，从而改变了如何通过复发性皮质脊髓网络有效地传递兴奋。总的来说，精细运动控制的产后出现与功能多样的皮质运动神经元之间的连通性相对扩大以及突触性质的改变有关，突触性质的改变可能导致较小的独立网络的出现，从而实现精细运动。突触模式和生理功能的这些变化为成熟与发育中的大脑能力增强提供了基础。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号