Emergence of Diverse Ripple-Firing Patterns via Synaptic Coupling Modulation in Hippocampal CA1 Neural Circuit Model

The hippocampal CA1 region is important for memory formation. However, how memory is encoded in hippocampal CA1 is still unclear. A previous study showed that emotional experiences in rats induce the experience-specific diversification of synaptic currents and ripple-firing events in hippocampal CA1. Ripple firing is a neural activity event observed in extracellular potentials and is generated by the synchronized firing of multiple neurons in hippocampal CA1 within approximately 50 ms. On the basis of this observation, we hypothesize that information related to episodic memory is encoded in ripple firing and that synaptic coupling strengths in hippocampal CA1 shape the diversity of ripple firing events. To verify this hypothesis, we construct a hippocampal CA1 neural circuit model and analyze how synaptic coupling strengths affect the diversity of ripple-firing events.