Second, during the passage into adolescence, individuals become better able to think about abstract ideas. For example, adolescents find it easier than children to comprehend the sorts of higher-order, abstract logic inherent in puns, proverbs, metaphors, and analogies. The adolescent’s greater facility with abstract thinking also permits the application of advanced reasoning and logical processes to social and ideological matters.
This is clearly seen in the adolescent’s increased facility and interest in thinking about interpersonal relationships, politics, philosophy, religion, and morality —topics that involve such abstract concepts as friendship, faith, democracy, fairness, and honesty.
Third, during adolescence individuals begin thinking more often about the process of thinking itself, or metacognition. As a result, adolescents may display increased introspection and self-consciousness. Although improvements in metacognitive abilities provide important intellectual advantages, one potentially negative byproduct of these advances is the tendency for adolescents to develop a sort of egocentrism, or intense preoccupation with the self. Acute adolescent egocentrism sometimes leads teenagers to believe that others are constantly watching and evaluating them, much as an audience glues its attention to an actor on a stage. Psychologistsrefer to this as the imaginary audience.
Taken from : The Gale Encyclopedia Of Psychology 2ND Edition - Bonnie Strickland