 It is often associated with the work of Arnold Gesell who, along with his colleagues at the Clinic of Child Development at Yale University, charted the development of thousands of children and described developmental milestones that were achieved in a developmental sequence.Learning programs based on the maturationist perspective usually focus on certain tenets of psychodynamic theories of development and progressive educational philosophy.These draw, for instance, from the work of Sigmund Freud as reflected in their emphasis on early experience for subsequent emotional, social, and cognitive development.