Wave propagation mediated by GABAB synapse and rebound excitation in an inhibitory network: a reduced model approach.

A reduction method is used to analyze a spatially structured network model of inhibitory neurons. This network model displays wave propagation of postinhibitory rebound activity, which depends on GABAB synaptic interactions among the neurons. The reduced model allows explicit solutions for the wavefronts and their velocity as a function of various parameters, such as the synaptic coupling strength. These predictions are shown to agree well with the numerical simulations of the conductance-based biophysical model.

Propagating activity patterns in large-scale inhibitory neuronal networks.

The propagation of activity is studied in a spatially structured network model of gamma-aminobutyric acid-containing (GABAergic) neurons exhibiting postinhibitory rebound. In contrast to excitatory-coupled networks, recruitment spreads very slowly because cells fire only after the postsynaptic conductance decays, and with two possible propagation modes. If the connection strength decreases monotonically with distance (on-center), then propagation occurs in a discontinuous manner. If the self- and nearby connections are absent (off-center), propagation can proceed smoothly. Modest changes in the synaptic reversal potential can result in depolarization-mediated waves that are 25 times faster. Functional and developmental roles for these behaviors and implications for thalamic circuitry are suggested.