Fig. 2.

Comparison of interburst frequencies for evoked IPSP barrages and intrinsic burst discharges in single PGN neurons.A, Compound IPSPs induced by glutamate applied locally to the PGN. Individual IPSPs can be distinguished and are indicated byarrows in the expanded trace. B, The initial IPSPs arrive at ∼650 Hz, but this frequency decreases steadily to ∼100 Hz. C, Interspike frequencies in a single PGN neuron generating a low threshold Ca²⁺spike mediated burst followed by tonic activity in response to the intracellular injection of a depolarizing current pulse.D, Overlap of the frequencies for IPSP and PGN spike generation demonstrating the similarity in these two distributions.