Graded persisting activity of heterogeneous neuron ensembles subject to white noises

Effects of distractions such as noises and heterogeneity in model parameters have been studied on the firing activity of ensemble neurons, each of which is described by the extended Morris-Lecar model showing the graded persisting firings with the aid of an included Ca 2+-dependent cation current. It has been shown that the graded persisting activity in an ensemble becomes more robust against distractions than that in a single neuron even when there are no couplings among neurons in the ensemble, which is due to the pooling (ensemble) effect. When the coupling is introduced, the synchronization of firings in ensemble neurons is increased, which is beneficial to firings of target neurons.