Long-term multielectrode registration of neuronal firing activity from rat cerebral cortex tissue in vitro

Activity-dependent processes are involved in neurite outgrowth and synaptogenesis. We expect that during neural network formation neuronal morphogenesis and synaptic connectivity are reciprocally dependent on the emerging bioelectric activity in the network. We want to study whether and how bioelectric activity is involved in the formation of network structure. A multielectrode recording facility has been constructed for the long-term registration of action potentials of individual neurons during network development in both organotypic and dissociated rat cerebral cortex tissue cultures. Long-term recordings of' action potentials with good signal-to-noise ratios have been obtained. Experiments to correlate these activity levels with quantitative data on neuronal morphological development are in progress. Uncorrelated periodic fluctuations at a time scale of about ten minutes have been observed.