Characteristics of period adding bifurcation without chaos in firing pattern transitions in an experimental neural...

Time variant signals received by a neuron were encoded into and output in the changing firing patterns. Recent investigations revealed that the firing patterns changed according to certain bifurcation principles. Thus, the bifurcation scenarios among various firing patterns were fundamental to the study of neural coding. In this study one of the previous theoretically proposed scenarios, period adding bifurcation without chaos, was experimentally confirmed to exist in real neuronal activities. The realistic bifurcation process possessed integer multiple patterns not found in previous theoretical reports. The observed bifurcation process was simulated in the stochastic neuronal model and the generation of the integer multiple patterns were related to the interplay between the internal noise and the dynamics of the neuron.