Isolated CA1 region slices behave identically to CA1/DG slices, ruling out an influence of DG on CA1 region excitability following a KA insult. (A) Cartoon showing the surgical separation of CA1. (B) Synchronized neuronal firing under Mg2+-free conditions in a slice following separation. (C) IBI of synchronized events in CA1 following separation and trisectioning (mean ± SEM, n = 6, one-way ANOVA). (D) Burst duration in CA1 following separation (mean ± SEM, * = p < 0.05, ns = p > 0.05, n = 6, one-way ANOVA. Sep = CA3 separation/deafferentation, Tri = trisectioned to leave only CA1).