Abstract
Microelectrode arrays (MEAs) are increasingly used to profile the development of synchronized activity in neural organoids, yet no organoid study has reported on the consistency of electrophysiological development across cell lines. Here, we used dissociated neural organoids derived from six cell lines on MEAs to characterize functional synapse development using multiple parameters across time. The dissociated organoids demonstrated increasing functional connectivity and network activity over time across all cell lines and plasticity in response to synaptic-like stimulation. Like the organoids they were derived from, dissociated organoid cultures contained a diverse mixture of cell types. These results demonstrate that dissociated cerebral organoids can generate functional neurons, akin to primary neuronal cultures from brain tissue, providing a scalable model for studies of neurodevelopment and synaptic function. Consistent with unguided differentiation, we observed variability in activity parameters linked to donor cell line and batch effects, which must be considered in experimental design.