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A neuronal spiking small-world network model of the hippocampus CA3 area is studied.The Izhikevich neuron model is adopted to be a single neuronal vertex in the network model.120 neurons are connected with small-world network algorithms.The number ratio of excitatory neurons to inhibitory neurons is nearly 5 to 1.The temporal-spatial sequences of neurons are simulated under the stimuli of Gaussian white noise input and sine input.The simulated spike trains are analyzed by the neuronal ensemble rate coding algorithm.When no stimulus applied to the neuronal network model,no ensemble activity is presented.When the two types of stimuli applied to the neuronal network model,the mean firing rate of the neuronal population is increased.When the external input stimulus is Gaussian white noise stimuli,according to the classical Hebb neuronal ensemble coding theory,increased firing rate of these neurons discharge also can be raised as a function of a neuronal ensemble.The neuronal ensemble can be used to characterize the external Gaussian white noise stimulation mode,and enabling the Gaussian white noise stimulation of neuronal ensemble encoding.Firing rate values with normalization are showed via color.When the stimulus is not acted on the network model,no ensemble is appeared.Neuron 1,26,29,31,47,53,59,82,92,104,107,and 117 form a neural ensemble during the Gauss stimulus.After stimulation mode,action potentials of hippocampus CA3 neurons are became sparse.When the external input stimulus is Gaussian white noise stimuli,the neuronal ensemble can be used to characterize the external sine stimulation mode,and enabling the sine stimulation of neuronal ensemble encoding.Firing rate values with normalization are showed via color.When the stimulus is not acted on the network model,no ensemble is appeared.Neuron 14,26,31,53,76,80,82,90,107,115,and 117 form a neural ensemble during the sine stimulus.After sine stimulation mode,action potentials of hippocampus CA3 neurons are became sparse.Neuron 26,31,53,82,107,and 117 are both active during the two types of stimuli.