Changes in spontaneous firing activity owing to transcriptional regulator depletion. (A) Experimental time line and schematic for the culturing and measurements of primary neurons using the multielectrode array (MEA). The recording diagram illustrates the different metrics collected by the MEA instrument. (B) Weighted firing rate of each condition based only on electrodes with activity greater than the minimum spike rate from days in vitro (DIV) 12 to 22. (C) Evoked metrics for each condition at DIV 18. Significance based on one-way ANOVA followed by Dunnett's posttest: (***) ≤0.001, (**) ≤0.01, (*) ≤0.05, (NS) not significant. (D) Example spiking patterns over a 200 sec recording period at DIV18.