The extent to which peer influences on substance use in adolescence systematically vary in strength based on qualities of the adolescent and his or her close friend was assessed in a study of 157 adolescents (Age: M = 13.35, SD = 0.64), their close friends and their parents assessed longitudinally with a combination of observational, analogue, sociometric, and self-report measures from early to mid-adolescence. The degree to which adolescents changed their levels of substance use in accord with their peers' baseline levels of use was predicted by a range of theoretically-salient factors including: observed teen lack of autonomy and social support in prior interactions with mothers, low teen refusal skills, and the level of social acceptance of their close friend. Findings suggest the importance of both internal factors (e.g., autonomy and relatedness struggles) and external factors (e.g., social status of friends) in explaining why vulnerability to peer influence processes may be much greater for some adolescents than others.

The role of rejection sensitivity as a critical diathesis moderating the link between adolescent relational stressors and depressive symptoms was examined using multi-method, multi-reporter data from a diverse community sample of 173 adolescents, followed from age 16 to 18. Relational stressors examined included emotional abuse, maternal behavior undermining adolescents’ autonomy and relatedness, and lack of support from close peers. As hypothesized, multiple relational stressors were found to predict the future development of depressive symptoms, but as hypothesized predictions existed primarily for adolescents who were highly rejection sensitive. Results are discussed in terms of a diathesis-stress model of depression and suggest that though relational stressors have previously shown consistent modest links to depressive symptoms, understanding pre-existing intrapsychic vulnerabilities of the adolescent may be critical to identifying the processes by which such stressors lead to depressive symptoms.

Pseudomature behavior—ranging from minor delinquency to precocious romantic involvement—is widely viewed as a nearly normative feature of adolescence. When such behavior occurs early in adolescence, however, it was hypothesized to reflect a misguided overemphasis upon impressing peers and was considered likely to predict long-term adjustment problems. In a multi-method, multi-reporter study following a community sample of 184 adolescents from age 13 to 23, early adolescent pseudomature behavior was linked cross-sectionally to a heightened desire for peer popularity and to short-term success with peers. Longitudinal results, however, supported the study’s central hypothesis: Early adolescent pseudomature behavior predicted long-term difficulties in close relationships, as well as significant problems with alcohol and substance use, and elevated levels of criminal behavior.

The broader context of relational aggression in adolescent romantic relationships was assessed by considering the ways such aggression emerged from prior experiences of peer pressure and was linked to concurrent difficulties in psychosocial functioning. Longitudinal, multi-reporter data were obtained from 97 adolescents and their best friends at age 15 and from adolescents and their romantic partners at age 18. Teens' relational aggression and romantic partners' victimization were predicted from levels of best friends' pressuring behaviors toward teens in an observed interaction as well as from best friends' ratings of how much pressure teens experienced from their peer group. Romantic partner relational aggression and teen victimization were predicted by pressure from teens' peer group only. Adolescents' romantic relational aggression and victimization were also associated with elevated levels of depressive symptoms and increased alcohol use. Results are discussed in terms of the connection of relational aggression in romantic relationships to the broader task of establishing autonomy with peers in psychosocial development.

The long-term social sequelae of adolescent depressive symptoms were examined in a multi-method, multi-reporter study of a diverse community sample of 179 adolescents followed from age 14 to 24. Even mild to moderate levels of early adolescent depressive symptoms strongly predicted loneliness, lower maternal relationship quality, and problematic interactions with romantic partners in adulthood, even after accounting for prior levels of social functioning and concurrent levels of adult depressive symptoms. Predictions were partially mediated via late adolescent avoidance of social interactions and poor maternal relationship quality. Results are interpreted as suggesting the potential impact of depressive symptoms on core tasks of adolescent social development, with potential implications for the need for treatment of even mild symptoms and their social concomitants.