Abstract <p>An achievement of modern neuroscience is the identification of neurons that are selectively involved in mediating various forms of human and animal behavior such as spatial navigation, object recognition and memory, and identification of conspecifics and members of other species, among others. Research on animals conducted by scientists at the Institute of Psychology of the Russian Academy of Sciences has demonstrated the specialization and highly selective activity of brain neurons in relation to various behavioral acts formed during learning. It has been shown that specialized neurons in the retrosplenial cortex of the cerebral hemispheres play a key role in the processes of learning and the execution of behaviors novel to the individual. A hypothesis has been proposed and substantiated that the nonspecific activity of these neurons—that is, their involvement in the execution of other acts, rather than those for which they are specialized—enables individuals to link behavioral acts together subjectively at the level of experience domains. This article examines the results of an empirical study of the spiking of single specialized neurons in the retrosplenial cortex, which was recorded in animals during the acquisition and performance of appetitive and defensive behaviors. The obtained data are interpreted from the perspective of the system-evolutionary approach, which is being developed based on P.K. Anokhin’s theory of functional systems.</p>