Membrane potential fluctuations determine the precision of spike timing and synchronous activity: A model study

作     者：Kretzberg, J Egelhaaf, M Warzecha, AK 

作者机构：Univ Bielefeld Fak Biol Lehrstuhl Neurobiol D-33501 Bielefeld Germany 

出 版 物：《JOURNAL OF COMPUTATIONAL NEUROSCIENCE》 (计算神经科学杂志)

年 卷 期：2001年第10卷第1期

页      面：79-97页

核心收录：

学科分类：0710[理学-生物学] 1001[医学-基础医学(可授医学、理学学位)] 07[理学] 071003[理学-生理学] 

基　　金：Studi-enstiftung des deutschen Volkes Deutsche Forschungsgemeinschaft, DFG 

主　　题：spike mechanism model spike timing synchronization reliability neural coding 

摘      要：It is much debated on what time scale information is encoded by neuronal spike activity. With a phenomenological model that transforms time-dependent membrane potential fluctuations into spike trains, we investigate constraints for the timing of spikes and for synchronous activity of neurons with common input. The model of spike generation has a variable threshold that depends on the time elapsed since the previous action potential and on the preceding membrane potential changes. To ensure that the model operates in a biologically meaningful range, the model was adjusted to fit the responses of a fly visual interneuron to motion stimuli. The dependence of spike timing on the membrane potential dynamics was analyzed. Fast membrane potential fluctuations are needed to trigger spikes with a high temporal precision. Slow fluctuations lead to spike activity with a rate about proportional to the membrane potential. Thus, for a given level of stochastic input, the frequency range of membrane potential fluctuations induced by a stimulus determines whether a neuron can use a rate code or a temporal code. The relationship between the steepness of membrane potential fluctuations and the timing of spikes has also implications for synchronous activity in neurons with common input. Fast membrane potential changes must be shared by the neurons to produce synchronous activity.