[Analysis of an instrumental motor act].

Different instrumental conditioned reactions were elaborated in dogs which suffered simultaneously from thirst and hunger. During the elaboration, not only external agents and the animal's own movements become conditioned stimuli but also any objects linked to these movements whose positive signal meaning is compared in the course of reinforcement with negative signal meaning of other objects and becomes differentiated. To achieve one and the same aim, different instrumental habits may be used, while the same habit may be used for achieving different aims. During instrumental conditioning any habit may acquire a generalized positive biological significance as a means of procuring.