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The same stimulus (a flash of light at a frequency of 6 Hz) was used in dogs to develop a food-related conditioned reflex reinforced by attractive food and an aversive conditioned reflex (avoidance/escape from paw stimulation) and differential inhibition to it (unavoidable series). This was followed by alternate experiments with selection of reinforcement and use of a differential stimulus (at a frequency of 0.6 Hz). In both series of experiments, dogs showed changes in food-related excitability (hunger, saturation). The numbers of investigative responses arising in response to the differential and positive conditioned stimuli and their latent periods were recorded. In conditions allowing selection (with electrodes on the paw and a pedal before the animal), dogs were found to differ in the extent to which one of these motivations dominated. Differential inhibition was less complete in those no-choice series in which the dominant motivation was used. In conditions allowing selection between the food-related and aversive reactions, responses to the differential stimulus depended on the balance between these motivations: the food-related motivation dominated after two days of starvation, while the aversive motivation dominated after satiation.

A defensive instrumental conditioned reflex (CR) successively to light flashes and to electrostimulation of the dorsal hippocampus (DH) and the caudate nucleus (CN) was developed in dogs with electrodes implanted in the brain. The contralateral of the DH, CN, the accumbent nucleus (AN) and the globus pallidus (GP) were tested for reproducibility of the instrumental movement. In a second series, the percent of evoked movements was compared with the EP arising in response to signal and test stimulation. The degree of participation of the tested structures in the motivational, signal, and executive components of the CR was elucidated. In the first series the movements were practically not reproduced. In the second series, in the presence of connections from the signal to the tested structures, they were elicited only by stimulation of the AN (15%). In the same series, given bilateral connections, movements in response to the stimulation of the basal ganglia occurred somewhat more frequently (up to 28%). The stimulation of the contralateral DH elicited movements in 75–100% of cases. When stimulation of the CN became a signal, the stimulation of the AN and the GP was accompanied in 40–100% of cases by movement. Thus, the AN participates to a minimal degree in the executive component of the CR. Participation of the basal ganglia in the signal component of the CR was greatest in the third series, which indicates that intrasystemic generalization is more effective than intersystemic.