The 4 major hypotheses created by John Flavell and Henry Wellman on how memory improves would be first the Piagetarian perspective compose of the nature-nurture, continuity or discontinuity and the active child. Second is the information-processing perspective compose of the nature to nurture still, mechanisms of change. Third would be the sociocultural perspective that would include nature to nurture followed by the influence of sociocultural context and mechanisms of change and lastly the dynamic-systems perspective including nature to nurture, the active child and mechanisms of change.