Department of Physiology, First Medical Faculty, Charles University in Prague, Albertov 5, 12800 Praha 2, Czech Republic.
Comput Math Methods Med. 2012;2012:595398. doi: 10.1155/2012/595398. Epub 2012 Jun 24.
Experimental and computational studies emphasize the role of the millisecond precision of neuronal spike times as an important coding mechanism for transmitting and representing information in the central nervous system. We investigate the spike time precision of a multicompartmental pyramidal neuron model of the CA3 region of the hippocampus under the influence of various sources of neuronal noise. We describe differences in the contribution to noise originating from voltage-gated ion channels, synaptic vesicle release, and vesicle quantal size. We analyze the effect of interspike intervals and the voltage course preceding the firing of spikes on the spike-timing jitter. The main finding of this study is the ranking of different noise sources according to their contribution to spike time precision. The most influential is synaptic vesicle release noise, causing the spike jitter to vary from 1 ms to 7 ms of a mean value 2.5 ms. Of second importance was the noise incurred by vesicle quantal size variation causing the spike time jitter to vary from 0.03 ms to 0.6 ms. Least influential was the voltage-gated channel noise generating spike jitter from 0.02 ms to 0.15 ms.
实验和计算研究强调了神经元尖峰时间的毫秒级精度作为在中枢神经系统中传输和表示信息的重要编码机制的作用。我们研究了在各种神经元噪声源的影响下，海马 CA3 区的多室锥体神经元模型的尖峰时间精度。我们描述了源自电压门控离子通道、突触囊泡释放和囊泡量子大小的噪声源的贡献差异。我们分析了尖峰之间间隔和尖峰发射前电压过程对尖峰时间抖动的影响。本研究的主要发现是根据其对尖峰时间精度的贡献对不同噪声源进行排序。最具影响力的是突触囊泡释放噪声，导致尖峰抖动从平均值 2.5 毫秒的 1 毫秒变化到 7 毫秒。其次是由囊泡量子大小变化引起的噪声，导致尖峰时间抖动从 0.03 毫秒变化到 0.6 毫秒。影响最小的是电压门控通道噪声，它产生的尖峰抖动从 0.02 毫秒变化到 0.15 毫秒。
