Longitudinal analysis of flexibility and reorganization in early adolescence: a dynamic systems study of family interactions.

A dynamic systems (DS) approach was used to study changes in the structure of family interactions during the early adolescent transition period. Longitudinal observational data were collected in 5 waves prior to, during, and after the transition. Boys (n = 149 families) were videotaped problem solving with their parents at 9-10 years old and every 2 years thereafter until they were 18 years old State space grids (a new DS method) were constructed for all families across all waves. Two variables indexing the variability of the family interactions were derived from the grids. As hypothesized, the DS variables revealed a significant quadratic effect related to a peak in variability at 13-14 years of age.