Modulating Network Dynamics Using a Pharmacological Paradigm of Long-term Potentiation on Cultured in vitro Hippocampal Networks

In the brain, the diversity of neural elements and their complex interactions give rise to emergent phenomena, including a wide variety of rhythmic oscillatory activity. A hallmark of the brain is that its constituents, excitatory and inhibitory neurons, organize into adaptive and robust circuits facilitating the formation of distinct patterns of electrical activity. The neurons in these circuits must have the ability to sculpt their output to respond to physiological perturbations that reflect inputs from the external milieu as well as to maintain a stable level of activity. Single cell dynamics will propagate throughout the circuit as these dynamics aggregate to represent an integrated system response. Here, we show how the effects of a pharmacological paradigm of long-term potentiation (LTP) on neurons within cultured hippocampal networks influence overall network dynamics. We use a grid of extracellular electrodes to study changes in network activity after this perturbation and show that the variability in overall spiking activity decreases after treatment suggesting that the network may be operating in a more regulated state. In addition we suggest that the observed increase in bursting activity may be a result of the recruitment of “errant” spikes into bursts, facilitating transmission of information flow throughout the neural circuit.