[New data on the correlation of the cardiac and motor components of the instrumental conditioned defensive reflex in dogs].

Correlation of heart rate (HR) and conditioned motor reaction (CMR) was studied in dogs with conditioned avoidance reflex by the V. P. Petropavlovskiĭ method. An increase of HR was shown in response to presentation of conditioned sound stimulus reaching maximum directly before CMR beginning. Immediately after the beginning of CMR and further against the background of continuous keeping of the paw in the safety zone, CMR greatly decreases. The CMR changes testify to a heavy weakening of classical conditioned reflex of fear as a result of kinesthetic afferentation signalling about successful keeping of the paw in the safety zone.