Nat. Neurosci. 19, 888–896 (2016); published online 23 May 2016; corrected after print 28 June 2016
In the version of this article initially published, the units on the x axis in Figure 3c were given as mm; the correct units are μm. At the end of the legend to Figure 7, the error bars were described as s.d.; they are actually s.e.m. in b and s.d. in c. In the third sentence of the Online Methods section on human cerebral organoids, 10% knockout serum replacement, 1% GlutaMAX and 1% MEM-NEAA should have been 20%, 1× and 1×, respectively. In the sixth sentence, 1% N2 supplement, 1% GlutaMAX and 1% MEM-NEAA should each have been 1×. In the eighth sentence, 6-mm dishes should have been 6-cm dishes, 0.5% N2 supplement and 0.5% MEM-NEAA should each have been 0.5×, and 1% B27 without vitamin A, 1% GlutaMAX and 1% penicillin/streptomycin should each have been 1×. In Supplementary Figure 10b, the graph lacked error bars. The errors have been corrected in the HTML and PDF versions of the article.