Fig. 1.

Extracellular field potential (LFP) recordings show large amplitude network events following application of high KCl. a Representative LFP trace (1 channel of MEA) shows development of synchronized network oscillations upon application of high (10 mM) KCl. The first 2 min of recording following high KCl application are not shown. Arrows indicate time intervals expanded in panels d–f. b Temporal structure of all burst events from a. Each row shows one event. The events are ordered chronologically from top to bottom and aligned by the peak of the amplitude. c Frequency and duration of the burst events from the entire course of recording. Duration of the events was computed by identifying contiguous time periods which had activity higher than sum of the mean and 50% of standard deviation, where mean and standard deviation were obtained from the 800 ms window that included burst and baseline activity. d Magnification from a shows network bursts with single spike at the beginning of epileptiform development. e Magnification from a shows network bursts at the maximum activity of the oscillations. f Magnification from a shows network bursts with multiple intraevent peaks at the end of the run