Sensory generalization in instrumental defensive reflexes in dogs.

Five dogs were preliminarily trained in the situation of classical defensive conditioned reflexes. The training sharply impeded the subsequent instrumental avoidance conditioning (with the stimulus applied to one leg and the avoidance movement accomplished by another leg). However, following the elaboration of the instrumental avoidance to one of the signals previously used in the classical situation, the other signals of the classical conditioned reflex evoked the instrumental avoidance reaction at once, without any preliminary training. When the animals which had been trained under "instrumental" conditions were brought back to classical situation they revealed an extreme inertness of manifestation of the instrumental avoidance reflex. In another experimental series the same dogs were trained to perform an escape reaction. When the stimulating electrodes were displaced to new receptive areas, most dogs made use of their previous experience and performed the acquired instrumental movement, thus escaping the electric shock.