Description of the firing pattern of respiratory neurons by frequency modulated interspike interval distributions.

The description of the firing pattern of respiratory neurons presented here is based on extracellular recordings and directed to the possible influence (facilitating of inhibiting effect) that the neuron might have upon others (output) as well as to the extend of influences that are received from other neurons (input). Developing such a description the spike generating mechanism of the neuron was in a first approach characterized by a frequency modulated gamma distribution. Using this approach an acceptable match between calculated and measured interspike-interval distribution was found although mostly not statistically significant. This non-significancy is most probably due to the choice of the simple gamma distribution as a first approach. However, applying this description it seems possible to retrieve statistical information about the interaction between neurons from extracellular recordings. Based on this description it is proposed to use modal spike frequency as well as the variance of the interspike interval distribution as estimates for the activity and the extent of activation of the neuron.