Using variable neuron thresholds and extended Hebb's rule in a neural network, a neuron device for simulating a nerve cell includes a threshold storage unit storing a threshold variable θ and threshold coefficients Δθ1 and Δθ2; an input reception unit receiving one or more input signal values at predetermined time intervals; an output unit outputting an output signal value “1” indicating that the neuron device is firing when the sum total s of received input signal values is equal to or greater than the value of the stored threshold variable θ, or a value “0” indicating that the neuron device is resting; and a threshold updating unit calculating Δθ1X+Δθ2(X−1) using the output signal value X and the stored threshold coefficients Δθ1 and Δθ2 and updating the value of the threshold variable θ stored in the threshold storage unit by increasing it by the calculation result.