A two-dimensional neuronal network with unidirectional coupling is constructed, and information transmission entropy is introduced to describe the directed information transmission. Hindmarsh-Rose neuron model is used to study mechanism of spontaneous generation of ordered waves such as spiral waves in the network. Numerical simulation shows that the network can appear spontaneously spiral wave, traveling wave, target wave and plane wave with appropriately selected strength of coupling and distance of unidirectional coupling. It is found that generation of various ordered waves is related to intermittently directed information transmission in the network. Entropy resonance occurs as single or multiple spiral waves appear in the network. Intermittently directed information transmission is also observed in the network with noise, inhibitory coupling and repulsive coupling when spiral wave and multiple spiral waves are spontaneously appeared. Self-sustaining long plane waves are observed for the first time. It is due to persistent strong directed information transmission in the network.

Effect of mechanical deformation on spiral waves in myocardial tissue is studied with Greenberg-Hastings cellular automaton. It shows that for stable spiral waves existing in a regular lattices system, physiological deformation leads to meandering but not breakup of spiral waves. However, pathological deformation results in breakup, meandering, or disappearance of spiral waves. Simulation results show that spiral waves are more sensitive to amplitude than to angular frequency of mechanical deformation. The quick recovery of a sportsman after hitting on breast and fibrillation coming from violent hitting on breast was explained.

Modified Bär model is used to study suppression of spiral wave. Methods of suppressing spiral wave by two-stage pulse force control are proposed. In the first stage,fast variable of the model is acted by a positive rectangular pulse force. In the second stage,direction of force is changed to the opposite or the force is acted on the slow variable. It shows that two-stage pulse control method is more efficient than one-stage method,and magnitude of the force is 38%~55% of the latter. It suggests that two-stage method of control of spiral wave can improve defibrillation efficiency.

Effect of conduction delay on dynamical behavior of spiral waves is investigated in Greenberg-Hastings model.It shows that in some cases dynamical behavior of spiral waves is not impacted by conduction delay.Changes in wavelength and wave speed,breathing spiral wave,multi-armed spiral wave,coexistence of spiral wave and anti-spiral wave are observed.Physical mechanisms of these phenomena are briefly analyzed.

Since refractory states of an excitable medium can be excited,depolarization is introduced into the Bar model.Depolarization effects on spiral waves are investigated.It shows that as threshold of depolarization and depolarization duration are chosen suitably,depolarization can induce drifting and meandering of spiral wave and even cause spiral wave moving out of boundary of the system.The dense spiral wave,two-arm spiral wave,twin speaks wave,multiple spiral wave and spatiotemporal chaos can also be generated with depolarization.Physical mechanism underlying these phenomena is discussed.

Suppression of spiral waves and spatiotemporal chaos in cardiac tissues described by LuoRudy 91 model are studied.We suggest a control strategy which applys calcium channel agonist to enlarge maximum conductivity of calcium current,and applys potassium channel blocker to reduce maximum conductivity of potassium current,for suppression of spiral waves and spatiotemporal chaos.It shows that the method can effectively suppress spiral waves and spatiotemporal chaos even if there exist defects without function of diffusion in a medium.The control mechanism is analyzed.