Effect of electrical coupling on two DA neurons with different levels of activation of NMDA inputs. Top: Low activation of NMDA inputs (PNMDA = 1.1 .10-6 cm/s). Bottom: High activation of NMDA inputs (PNMDA = 1.7 .10-6 cm/s). Strong coupling can convert these neurons to bursts. Blocking of coupling converts activity to single spiking again.