(A) Phase contrast image ( × 200) showing the enriched neuronal cultures that were used in the experiments. (B) Illustrates immunocytochemistry of the neuronal culture with βIII-tubulin stained neurons (green) and DAPI (blue) as cellular counterstaining (scale bar: 50 μm). (C) Confirms neuronal and neurotransmitter markers by staining for synapsin, glutamate, MAP2ab, and GABA (red), DAPI (blue), and βIII-tubulin (green) (scale bar: 50 μm). (D) Illustrates cortical markers, resulting as a default regional identity after neural induction by staining for FOXG1, OTX1, TBR1, and REELIN (scale bar: 25μm). βIII-tubulin, Beta-III-tubulin; DAPI, 4',6-diamidino-2-phenylindole; MAP2ab, microtubule associated protein 2ab; GABA, gamma-aminobutyric acid; FOXG1, Forkhead Box G1; OTX1, orthodenticle homeobox 1; TBR, T-Box, Brain 1.