Removing Type I–II synapses degraded synchrony and burst structure. Peak height decreased (B), burst width narrowed until 80% of Type I–II synapses were removed, when Type I activity was not completely silenced and bursts became bimodal (C), burst shape became more sloped (D), and Type I cells maintained their activity long after Type II cells were silenced (E). (A–E) Raster plots (A, top panel), network firing rates (A, bottom panel) and bursting metrics (B–E, boxplots as in Fig. 2) for an excitatory heterogeneous network with 25% of synapses removed (A) or with 5% of synapses successively removed (B–E); all removed synapses were Type I–II.