By means of the classical alimentary secretory method, a study was made of the characteristics of formation and preservation of complex systems of conditioned reflexes in dogs with a preliminarily lesioned cortex of the auditory analyser. It has been shown that a rhythmic-mozaic stereotype of conditioned reflexes to acoustic signals can be elaborated in the operated dogs, although conditioned activity is on a very low functional level. However, integration of two complex stereotypes into one single system is not achieved. The formation of a new stereotype in the operated dogs, in contrast to the intact animals, is not accompanied by an enhanced functional state (tone) of the brain, which points to an insufficiency of the self-regulating mechanisms of the cerebral cortex. It is suggested that special activating mechanisms which participate in controlling the functional state of the auditory system, are present in the cortical structures of the auditory analyser.