ABSTRACT
The preschool years can be thought of as a developmental period generally dominated by dynamic and robust progressive processes, with an emphasis on growth, expansion, "construction," and "blossoming" that will later be pruned and tuned with continued maturation and experience. Although there is expansive and positive evidence about the dynamics of brain development during the preschool years, it also is clear that the impact of poor environmental conditions, especially abusive conditions, can have particularly deleterious effects on children of this age level. Preschool experiences as ameliorators of environmental deficiencies have been advocated for over 30 years, since the initiation of Head Start, and there have been many studies reporting some areas of long-term effectiveness. Extensive research on the brain development of young children who are preschool program participants has not been conducted, so it is unclear how brain synaptic connections or other changes in brain structure and function may be promoted by the programs.
