[Participation of the dopamine-reactive system of the caudate nucleus in regulating instrumental conditioned reflexes of various degrees of complexity].

Administration of dopamine into the dorsal part of the caudate nucleus' head hindered the instrumental feeding conditioning with tonic form of motor response in cats. In preliminarily conditioned animals, dopamine impaired the tonic phase of the conditioned response and, consequently, made them loose the ability to synchronize the food-seeking motor response with the moment of food reinforcement. Special series of experiments were performed to study the character of motor disturbances revealed in the tonic phase of the instrumental conditioning as well as their relation to the level of initial motivation. Role of the caudate nucleus dopamine-reactive system in the mechanism of delayed inhibition, is discussed.