Fig. 4

A spreading pattern (C) governed by the space–time model (3) and (4) with a radially symmetric synaptic connectivity kernel given by (12) and a Dirichlet boundary condition \(u_{\text{BC}}=0\) on a domain of size \([-L,L] \times [-L,L]\). The corresponding interface dynamics is shown in (D). Rows (A) and (B) show the components of the gradient z in the x and y directions, and these are used to compute the activity of the neuronal tissue shown in row (C). Parameters are \(\kappa=0.05\), \(a_{1} =3.55\), \(a_{2} = 3\), \(b_{1} = 2.4\), \(b_{2} = 3.2\), \(c=10\), and \(L=5\pi\)