ABSTRACT
The development of the mammalian central nervous system is highly complex: during ontogenesis of the CNS, very specialized morphological and biochemical changes occur that may be profoundly altered by changes in the physical or chemical milieu. Although this chapter will focus almost exclusively on changes in the chemical environment (i.e., exposure to xenobiotics), it is important to realize that changes in the physical environment (e.g., contact with the mother or siblings) may also have profound effects. These latter changes, although initiated by physical forces, may involve physiological mechanisms. These may then serve as the antecedent chemical stimulus for alterations in CNS development.
