Neuron-type conducting polymers have been prepared electrochemically. The pattern of the network of neuron-type conducting polymers depends on the experimental or environmental conditions. The weight of the path in the network depends on the shape and the number of the path between the sites. If this network of conducting polymer is packed to produce a new device, the device will contain the environmental conditions. Furthermore, the device has the characteristics of a synapse; it works as neuron device. It is proposed that the conducting polymer gel be used so that a learning effect is added to the path of the network. In the process of swelling or shrinking under some solvents, the dopant moves in or out of the conducting polymer Gel. However, it has been found that the dopant in the path does not easily move out even in the poor solvent when an a.c. voltage of one polarity has been applied to the conducting polymer under the liquid-phase doping. Therefore, this treatment is used in the learning effect or the memory effect, i.e. the learning current or voltage is applied to the neuron-like network conducting polymer doped in liquid phase, dry it and drop the poor solvent on the path. Hence, this network has many paths with various resistivities.