To characterize a property of firing prolongation by repetitive input cycles, and a residual effect after a decasecond intermission, we studied striatal neurons in slice and confirmed in vivo. The striatum neurons showed a residual firing response of increasing duration when exposed to repetitive optogenetic photostimulation. The prolonged firing persisted after a 20 sec intermission. Repetitive photostimulation to patch-clamped neuron induced residual depolarization with a decay of 8.6-sec half-life time and firing prolongation, but current injection to the soma did not. Ryanodine receptor antagonists significantly decreased development of prolongation. On the other hand, a ryanodine receptor agonist increased the firing development. Local anesthetics, including procaine, and lidocaine canceled the residual firing. These phenomena indicate that striatal neurons hold their internal state in second-order timescale through ryanodine receptor mediated calcium release to count inputs cumulatively.