The combination of two technologies—induced pluripotent stem cells and high-density microelectrode arrays—offers an unprecedented platform to study human brain activity in detail outside the body.    Back in 2006, Prof. Yamanaka and colleagues revealed a technique to reprogram adult skin cells into embryonic-like cells called induced pluripotent stem cells or iPSCs. This Nobel Prize winning technology enables access to human neurons derived from adult blood or skin cells in a high-throughput manner, thus opening up the possibilities to study neurological…