A reduced model for medial entorhinal cortex stellate cell: subthreshold oscillations, spiking and synchronization
نویسندگان
چکیده
Entorhinal cortex layer II stellate cells display subthreshold oscillations (STOs). We study a single compartment biophysical model of such cells which qualitatively reproduces these STOs. We argue that in the interspike interval (ISI) the seven-dimensional model can be reduced to a three-dimensional system of equations with well differentiated times scales. Using dynamical systems arguments we provide a mechanism for generations of STOS. This mechanism is based on the “canard structure”, in which relevant trajectories stay close to repelling manifolds for a significant interval of time. We also show that the transition from subthreshold oscillatory activity to spiking is controlled in the ISI by the same structure. The same mechanism is invoked to explain why noise increases the robustness of the STO
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