Figure 13.

Simulations of the stochastically coupled FHN model with multiplicative noise system with spatial-extended structure (69). The same parameters as in (71) are taken and $d_{{\gamma }_i}=d_{\gamma }=1$ and ${\widehat{\gamma }}_i=\widehat{\gamma }=1$ for all i. Homogeneous initial conditions $u_i\left(0\right)=-2$ and $v_i\left(0\right)=0.5$ are adopted for all $i=1,\dots ,N$. (a–d) show the simulation with different ${\sigma }_{\gamma }=0,0.3,0.6$ and $1.0$, where ${\sigma }_{\gamma }$ is the noise coefficient at all the grid points, namely ${\sigma }_{{\gamma }_i}={\sigma }_{\gamma }$ for all i.