Fig. 3.

Systems with and without stable synchrony. (a) Phase lag as a function of time for systems of two mutually coupled nodes with continuous state variables under fluctuating transmission delays. The system with antisymmetric coupling (Eqs. 1 and 2) remains synchronous with a phase lag close to 0.5 (black curves). In the system with symmetric coupling (Eqs. 5 and 6) the phase lag between the oscillating nodes is not stable against fluctuations (gray curves). (b) Same as in a for systems with discrete (Boolean) state variables with antisymmetric coupling (Eqs. 3 and 4) and symmetric coupling (Eqs. 7 and 8).