[The model of the reward choice basing on the theory of reinforcement learning]. 
We developed the model of alimentary instrumental conditioned bar-pressing reflex for cats making a choice between either immediate small reinforcement ("impulsive behavior") or delayed more valuable reinforcement ("self-control behavior").  Our model is based on the reinforcement learning theory.  We emulated dopamine contribution by discount coefficient of this theory (a subjective decrease in the value of a delayed reinforcement).  The results of computer simulation showed that "cats" with large discount coefficient demonstrated "self-control behavior"; small discount coefficient was associated with "impulsive behavior".  This data are in agreement with the experimental data indicating that the impulsive behavior is due to a decreased amount of dopamine in striatum.