Chapter 6 Critical and Sensitive Periods in Neurobiology

Abstract

Publisher Summary This chapter reviews studies on critical periods and sensitive periods from a theoretical perspective in an attempt to trace the conceptual origins of these terms, to define the contexts within which they have been used, and to determine the heuristic value of these concepts to modern neurobiology. The study of critical periods and sensitive periods involves not only practical aspects but also theoretical inferences into the organizational processes that underlie the functional specificity of the nervous system. Despite the wide variety of mechanisms involved during critical periods and sensitive periods, phenomenologically similar ontogenetic processes, and the ways in which they are influenced by external factors, one may arrive at certain theoretical generalizations. First, the timing and duration of these periods appear to be related to different rates of development across different species; however, the underlying mechanisms are probably similar, thus allowing across species generalizations. Second, these periods reflect the activity of multiple organizational processes. These processes have different or overlapping critical periods and sensitive periods in a given species.