Dynamic responses of pair of identical neurons. PNMDA = 1.58 .10-6 cm/s. A: Gc = 0 ; B: Gc = 2 .10-5 S/cm2 ; C: Gc = 6 .10-5 S/cm2 ; D: Gc = 7 .10-5 S/cm2 . Left column: Membrane potential of one neuron. Right column: Phase portraits for membrane potentials (VD1, VD2) as a function of increasing coupling strength. Each phase portrait corresponds to firing patterns on the Left. Gc = 0 - single spiking with phase shift.; Gc = 2 .10-5 - 6 .10-5 S/cm2 - different kinds of bursting activity; Gc = 7 .10-5 S/cm2 - completely synchronized oscillations.