Electrically coupled neurons communicate through channel assemblies called gap junctions, which mediate the transfer of current from one cell to another. Electrical synapses ensure spike synchronization and reliable transmission, which influences bursting patterns and firing frequency. The present study concerns an electrically coupled two-neuron network in the gastropod mollusc, Lymnaea stagnalis. The neurons, designated Visceral Dorsal 1 (VD 1 ) and Right Parietal Dorsal 2 (RPD 2 ), are peptidergic, innervate aspects of the cardio-respiratory system, and show strong coupling, such that they fire synchronously. Using dual sharp-electrode current-clamp recording and morphological staining in isolated brain preparations, the hypothesis that the electrical synapse is necessary for accurate network output was tested. We found that both cells make extensive projections within and out of the brain, including across the visceral–parietal connective, which links VD 1 and RPD 2 . Cutting this connective uncoupled the neurons and disrupted the firing rate and pattern of RPD 2 more than VD 1 , consistent with VD 1 being the master and RPD 2 the follower. The electrical synapse was inhibited by select gap junction blockers, with niflumic acid and 5-nitro-2-(3-phenylpropylamino) benzoic acid decreasing the VD 1 →RPD 2 and RPD 2 →VD 1 coupling coefficients, whereas carbenoxolone, α-glycyrrhetinic acid, meclofenamic acid, and quinine were ineffective. There was little-to-no impact on VD 1 ↔RPD 2 firing synchrony or frequency when coupling was reduced pharmacologically. However, in the presence of gap junction blockers, suppressing the activity of VD 1 by prolonged hyperpolarization revealed a distinct, low-frequency firing pattern in RPD 2 . This suggests that strong electrical coupling is key to maintaining a synchronous output and proper firing rate.