hiPSC-derived neurons are amenable to a variety of functional analyses. Given that perturbations in neuronal excitability are thought to underlie many psychiatric disorders (Anticevic and Murray, 2017), the ability to investigate excitability and network activity of human cells is a crucial step for understanding the disease. Whole-cell patch-clamp electrophysiology provides single-cell measurements of neuronal activity, with details on excitatory and inhibitory synaptic inputs. This is crucial for determining dysfunctions in particular channels implicated in alcoholism (for example, GABAA (Lobo and Harris, 2008). Several techniques are available for examining neuronal network activity, such as with microelectrode array (MEA) and Ca2+ imaging. MEAs can be used to study population activity at different time points throughout development. hiPSC-derived neurons are cultured directly on top of microelectrodes lining the bottom of the plate, and can be subjected to field stimulation or photostimulation techniques (Hales et al., 2010; Obien et al., 2015). Calcium imaging, using cell permeable dye (e.g. Fluo4-AM) or a genetically encoded indicator (e.g. GCaMP6) (Grienberger and Konnerth, 2012), offers single cell resolution as well as information on network activity. Compared to electrophysiology
