Wyman R
Biophys J. 1965 Jul;5(4):447-71. doi: 10.1016/S0006-3495(65)86729-7.
A probabilistic method of analysis of spike trains is presented which provides a complete statistical description of spike sequences and allows the elucidation of some of the properties of the neural interconnections producing the output patterns. The flight motor system of the blowfly, Calliphora terraenovae, is analyzed by this method. Individual motor units show large, non-serially correlated, cycle-to-cycle variations in frequency superimposed upon long term frequency trends. These trends are apparently not generated by averaging the cycle-to-cycle variations in input excitation over a long time period. The different motor units share the same short term input excitation and the excitation causing long term trends. Units in different muscles show no preferred phase or latency relationships; they maintain similar frequencies but their phases drift through all possible values. Frequency control without phase control may be accomplished by shared excitation with a total input frequency many times the output frequency. Units in the same muscle maintain strong phase relationships. Constant phase relationships during variations in frequency may, among other models, be due to reciprocal inhibition or a common linearly rising input. Sensory feedback cannot account for the degree of phase or frequency regulation shown. Thus central patterning of the output sequence is necessary, as in the locust, and the two flight systems can be considered as integradable evolutionary variations.
本文提出了一种分析脉冲序列的概率方法，该方法能对脉冲序列进行完整的统计描述，并有助于阐明产生输出模式的神经互连的某些特性。利用这种方法对新陆原伏蝇的飞行运动系统进行了分析。单个运动单位在长期频率趋势之上，表现出频率上大的、非序列相关的逐周期变化。这些趋势显然不是通过长时间平均输入激励的逐周期变化而产生的。不同的运动单位共享相同的短期输入激励以及引起长期趋势的激励。不同肌肉中的运动单位没有表现出优先的相位或潜伏期关系；它们保持相似的频率，但相位会漂移到所有可能的值。在总输入频率是输出频率许多倍的共享激励下，可以实现无相位控制的频率控制。同一肌肉中的运动单位保持着很强的相位关系。在频率变化期间保持恒定的相位关系，在其他模型中，可能是由于相互抑制或共同的线性上升输入。感觉反馈无法解释所显示的相位或频率调节程度。因此，如同在蝗虫中一样，输出序列的中枢模式形成是必要的，并且这两种飞行系统可被视为可整合的进化变体。
