GABA_AR modulates the bursting propensity of subicular IB cells.

<p><b>A:</b> Definition of burst ratio of IB cells responses to depolarising current injection. This IB neuron generated 4 bursts made of 2 spikes (black arrowheads), followed by the generation of a single action potential (grey arrowhead). Therefore, the number of spikes generated during burst-firing was 8 on a total of 9, thus yielding a burst ratio of 0.89. The burst indicated by the horizontal arrow is shown at expanded time scale in the inset on the left, where the black arrow points at the depolarizing membrane potential fluctuation giving rise to the second spike generated within the burst. Bath-application of picrotoxin (100 µM) decreased the burst ratio of this IB neuron to 0.33. <b>B:</b> Summary of the parameters used to quantify the bursting behavior of PCs and their changes by pharmacological blockade of GABA_AR.