Functional Connectivity of Neural Network in Dissociated Hippocampal Culture Grown on Microelectrode Array

Dissociated neural cultures are used as convenient experimental models to study basic mechanisms of brain signal processing, memory, learning and synaptic plasticity in neuronal networks.Evaluation of short-term and long-term memory in hippocampal cultures requires simultaneous multisite recording of signals and bioelectrical stimulation.The aim of the investigation was to reveal the characteristic features of neuronal network plasticity in the model of primary hippocampal cell cultures, to study the stability of spontaneous and stimulus-induced changes in spiking patterns of cultures.Materials and Methods.Long-term changes in functional connectivity characteristics of spikes propagating in the neural network of hippocampal cultures grown on microelectrode arrays were evaluated.It was investigated how low-frequency stimulation (0.1-0.5 Hz) lying in the frequency band of spontaneous bursting activity altered functional connections in the network at different time scales.Results.Low-frequency stimulation of hippocampal cultures grown on microelectrode arrays was found to induce reconfiguration of the network connectivity.This effect could be preserved during tens of minutes.On the time scale of hours, stimulation-induced connectivity pattern disappeared due to spontaneous changes.