These improvements occur in five areas during adolescence:. Freud believed that the psychological disturbances associated with youth were biologically based and culturally universal while Erikson focused on the dichotomy between identity formation and role fulfillment. The age at which particular changes take place varies between individuals, but the changes discussed below begin at puberty or shortly after that and some skills continue to develop as the adolescent ages. Despite the common [ according to whom? How children and adolescents spend their time:
Hormones play an organizational role, priming the body to behave in a certain way once puberty begins,  and an active role, referring to changes in hormones during adolescence that trigger behavioral and physical changes. Girls 15 to 19 have higher rates of gonorrhea than any other age group. Development, Health Disparities, Stigma, and Resilience".
Nonetheless, new legal privileges converge with shifting social expectations to usher in a phase of heightened independence or social responsibility for most legal adolescents.
These relationships become significant because they begin to help the adolescent understand the concept of personalities, how they form and why a person has that specific type of personality. Within a clique of highly athletic male-peers, for example, the clique may create a stronger sense of fidelity and competition. Research since reveals self-examination beginning early in adolescence, but identity achievement rarely occurring before age A Lifespan View 5th ed. Adolescents are much better able than children to understand that people do not have complete control over their mental activity.
During adolescence, myelination and synaptic pruning in the prefrontal cortex increases, improving the efficiency of information processing, and neural connections between the prefrontal cortex and other regions of the brain are strengthened. The degree to which adolescents are perceived as autonomous beings varies widely by culture, as do the behaviors that represent this emerging autonomy.