神经网络中的混乱,具有平衡的刺激和抑制活动
C van Vreeswijk1, H Sompolinsky
1Racah Institute of Physics and Center for Neural Computation, Hebrew University, Jerusalem, 91904 Israel.
概括
神经网络表现出混乱的动态,由于平衡的激发和抑制,导致对刺激的快速反应. 这解释了在动物皮层神经元中观察到的不规则的发射模式.
科学领域:
- 神经科学是一个神经科学.
- 计算神经科学是一种神经科学.
- 理论神经科学 理论神经科学
背景情况:
- 行为动物中的皮层神经元会出现暂时不规则的尖.
- 这种发射不规则背后的原因及其功能意义仍然不清楚.
研究的目的:
- 探讨神经元发射的时间变化源于激发性和抑制性输入之间的平衡.
- 探索这种平衡对神经处理和网络动态的影响.
主要方法:
- 关于神经元网络动态的理论研究.
- 模拟具有稀疏,强大的突触连接的激发性和抑制性神经元群体的大型网络.
- 在恒定的外部输入下分析网络行为.
主要成果:
- 在这种网络中,激发性和抑制性输入之间的近似平衡自然会出现.
- 平衡状态的特点是强烈混乱的动态,即使有恒定的外部输入.
- 尽管单个神经元具有非线性动态,但该网络对刺激有线性反应.
- 该网络在时间尺度上对外部刺激做出反应,比单个神经元集成时间更快.
结论:
- 均衡的激发和抑制是皮层神经元发射时间变化的可信来源.
- 在平衡的网络中,混乱的动态可以导致高效和快速的信息处理.
- 这些发现表明皮质网络如何实现复杂的动态和响应性行为的机制.
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