Inside the simple burst neuron block. (A) A single-compartment neuron represented by adding currents through each ligand-binding receptor (for AMPA, Gly, NMDA, and a T-type Ca++ channel) to the Hodgkin-Huxley equations for the voltage-gated channels (for details, see Miura and Optican, 2006). Note that Gly acts at both the strychnine-sensitive glycine receptor (GLYCINER) and the co-agonist cite of the NMDA receptor. (B) Burst neuron simulating GABA-ergic OPNs. Note that OPN output goes only to GABAAR, and not to the co-agonist site on the NMDAR.