Figure 8.

iPSCMNs action potential profiles mature with age. A, Representative spikes at early and late time points after injection of depolarizing current. Note the presence of the afterhyperpolarization in the action potential (AP) generated at the late time point. B, AP duration (measured at half-maximum peak amplitude) significantly decreases as motoneurons mature (Kruskal–Wallis one-way ANOVA on ranks, p < 0.05 for early (n = 11) versus late (n = 10) and middle (n = 8) versus late. Early, 9–14 d in culture; middle, 21–29 d in culture; late, 37–43 d in culture.