Single excitable cells are capable of various rhythmic firing.Some neurons,especially the sensory neurons,encode the external stimulus into the temporal patterns of firing series.The dynamics as well as the biophysical mechanisms of such rhythmic patterns attract the attentions of scientists from a number of fields,since the elucidation of them may be of great help to further understanding of neuronal information processing.Physiological experimentations and nonlinear theoretical analysis revealed the generation of particular firing rhythms and the transition among different rhythmic patterns,including periodic,chaotic,stochastic patterns and the bifurcation processes between them.On the other hand,the capability of single cell in information encoding is limited.Brain functions are realized via collective activities formed in ensembles.The coherent excitation of excitable cell assembly underlies pattern formation and higher brain functions could be investigated from the transition of each single unit in the neuronal network.The significance of the rhythm transition of single cells could be more adequately examined in the study of the formation of collective behaviors.