Abstract: The nervous systems achieve information processing and biological functions with dynamic electronic activities. The firing rhythms and spatiotemporal behaviour of nervous systems are the dynamical characteristics of the achievement of the functions. Combined electrophysiological experiments with theoretical models, diverse rhythm patterns such as periodic, chaotic, and stochastic firing patterns, and complex rhythm transition regularities modulated by the external signal, parameter, and noise were identified with help of the bifurcations. The rhythm information (blood pressure signal and pathological pain) coding mechanism for sensory nervous system and the effect and different classes of synaptic noise to enhance information transmission capability in single pyramidal neurons of the brain were identified. The results are helpful to enhance the ability to enhance information detection and provide guidance for analgesia. The drug-modulated spiral waves/epilepsy observed in the brain cortex and synchronization transitions of firing patterns/abnormal functions of motor network were interpreted with the dynamics of single neurons such as the bifurcations and the fast-slow dynamics of the bursting pattern, which provide the way to modulate the functions of the nervous system. The spatiotemporal behaviour of the functional network of brain of the patients with autism can be acquired with big-data analysis and it was that the synchronous degree between brain regions related to the symptoms of autism reduced, which may be used as the potential diagnostic criteria. The results of the present paper provide new experimental observations, new mathematical model, new analysis method, and new viewpoints, and present identification of the complex dynamics of nervous system and deep understanding for the information processing mechanism and abnormal biological functions/diseases, which are of important scientific values and potential applications.