对基于行为的神经模型与同步突触输入的神经元模型的子值变量的准确分析.
Logan A Becker1,2, Baowang Li1,2,3,4,5, Nicholas J Priebe1,2,4
1Center for Theoretical and Computational Neuroscience, The University of Texas at Austin, Austin, Texas 78712, USA.
Physical review. X
|June 24, 2024
概括
新皮层神经元表现出变异性. 本研究开发了一个框架来分析下值电压变化,发现现实的变化需要强大的突触驱动或弱输入同步,挑战异步状态理论.
科学领域:
- 计算神经科学是一种神经科学.
- 系统神经科学 系统神经科学
- 理论神经科学 理论神经科学
背景情况:
- 新皮层神经元活动显示出显著的变化,即使具有相同的刺激.
- 异步状态假设表明独立的神经元发射,最大限度地减少同步的突触输入.
- 现有的模型解释了尖端变异性,但没有解释值以下的膜潜力变异性.
研究的目的:
- 开发一个分析框架来量化基于导电性的神经元中的下值电压变化.
- 研究突触输入同步对神经元变异性的影响.
- 确定神经网络中现实的下值变化的条件.
主要方法:
- 利用可交换性理论,使用基于跳跃过程的突触驱动器来建模输入同步.
- 在一个简化的神经元模型的静止反应上进行了瞬间分析 (全或无导电量,忽略后螺旋重置).
- 导出了膜电压前两个静态时刻的精确,闭式表达式.
主要成果:
- 异步模式只能产生现实的下值变化 (4-9 mV2),只有有限数量的强突触,与乳头输入相一致.
- 通过密集的皮层-皮层输入来实现现实的可变性,需要结合弱,非零输入同步.
- 神经可变性减少到零,没有同步的缩放极限与消失的突触重量,不管平衡状态假设.
结论:
- 新皮质神经元中的下值电压变化对突触输入特征敏感,包括同步性.
- 现实的下值可变性可能取决于特定的网络结构 (例如,强大的thalamic驱动器) 或弱的输入同步.
- 这些发现挑战了神经网络中异步状态的平均场理论的理论基础.
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