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If you are referring to neural differentiation of human ES/iPS cells to generate neural progenitor cells (NPCs), the most common methods involve either embryoid body or monolayer culture systems. The same approaches have been used to generate progenitors from all three germ layers (ectoderm, mesoderm, endoderm), but specific growth factors or small molecules are normally required to direct differentiation to a particular lineage.
If you are referring to downstream differentiation of hPSC-derived NPCs to different types of neurons and glia, NPCs can be patterned to produce neurons from different regions of the nervous system, such as cortical neurons, midbrain dopaminergic neurons, or spinal motoneurons. In this case, specific patterning factors (e.g. FGF-8, SHH, RA, etc.) are usually required in addition to the initial neural induction step. Region-specific patterning using specific sets of growth factors or small molecules is also used to generate anterior or posterior endoderm derivatives from hPSC-derived definitive endoderm.