disease 37,38 and to generate cortical interneurons 39. An alternative protocol, that combined dual SMAD inhibition with retinoid signaling led to a 95% efficiency of neuronal differentiation 40 and has been used to model Alzheimer disease and schizophrenia 41–43. In addition, many more variations of 2D protocols exist, which have been developed and successfully used to generate specific neuronal subtypes, such as GABAergic inhibitory neurons 44, glutamatergic neurons 44, and hippocampal granule neurons 45 (see table 1 for more information on different monolayer protocols).
