Figure 8. Synchronicity of GABAergic input to Cajal–Retzius cells (red) and stratum lacunosum-moleculare interneurons (blue) in the presence of 4-AP.

A, anatomical recovery of simultaneously recorded neurons in minislices. Notice the typical appearance of the Cajal–Retzius cell compared to a multipolar interneuron. B, left: spontaneous epileptiform currents recorded in voltage-clamp from a Cajal–Retzius cell and an interneuron (V_hold= 0 mV). Notice that the large events in the simultaneously recorded neurons appear time locked. Insets show epileptiform currents at slower time scales. Right: cross-correlogram of the currents measured in the two cell types. C, synchronization was observed also in current-clamp conditions: notice the large bursts recorded in a pair of simultaneously recorded Cajal–Retzius cell and interneuron. See also Supplemental Figs S2 and S3.