The current paper utilizes a bifactor modeling approach to evaluate the structure of attention-deficit/hyperactivity disorder (ADHD) in adulthood and assess developmental continuity of ADHD structure between childhood and adulthood. The study compared traditional one-factor, two-factor, three-factor, and second-order factor models of ADHD with a…

Two experiments used a formal model of developmental discontinuity derived from catastrophe theory to test whether the transition from Rule I to Rule II on the balance scale task proceeds discontinuously from ages 6 to 10, focusing on five catastrophe flags. Found that bimodality, inaccessible region, hysteresis, and sudden jump were clearly…

The conceptualizations of morphogenic processes suggested by systems theorists provide a useful framework for describing growth and development in complex adaptive self-directing organisms. These processes involve changes in (1) a system's structure, state, or functioning; (2) discontinuities in development; and (3) at least two kinds of…

Many children and adolescents, in Boston and elsewhere, experience drastic incongruities between their home, school, and community environments. Arguing that after-school programs can help to unify these disparate worlds, thereby fostering a sense of continuity for youth and aiding their development as learners, this report shows how best to…