Development of L.S. Vygotsky's Ideas About the Sensitive Periods of Ontogenesis in Modern Home and Foreign Psychology

The present state of the problem of the sensitive periods of ontogenesis is under discussion in this article. The phenomena of the biological hours, the emulative exclusion and the environmental filter are analyzed. The author explains her model of the bio-social balance, where the sensitive periods are regarded as dynamic unities of biological and social factors that influence on child's ontogenesis and make the most favorable conditions for the development of certain mental functions. An analysis of the proposed parameters is given for the further diagnostic of the sensitivity. The author gives proof to possibility of application of the motivation readiness criterion for the acceptance of the external influence as the diagnostic criterion. The study made it apparent that the selective removal of biological or social factors (as in mentally retarded children) and also the disruption of their balance in ontogenesis cause different disorders of the age sensitivity and of the child's mental development on the whole.